The defendant shall pay to the plaintiff 1 1,687,260 won, 1,648,773 won, and each of them shall be paid 5% per annum from November 15, 2010 to November 25, 2014, and 20% per annum from the next day to the day of full payment.

2. The plaintiffs' remaining appeals are dismissed.

3. 19/20 of the total litigation costs shall be borne by the Plaintiffs, and the remainder by the Defendant, respectively.

4. The part on which money is paid under paragraph (1) may be provisionally executed.

A. A. Around December 26, 2001, approximately KRW 9,294,326 square meters in the area of a housing site development district in Sungnam-si, Sungnam-si was designated as a planned housing site development district by the Ministry of Construction and Transportation on December 26, 2001. The Korea Land Corporation, along with the Korea National Housing Corporation, Sungnam-si, etc., was the executor of the “Ssungnam-si Housing Site Development Project” (hereinafter “instant project”). With respect to the instant project, the approval of the housing site development plan on December 30, 2003, and the approval of the housing site development implementation plan on December 30, 2004, respectively, was granted from May 2005 to December 13, 2009.

B. As part of the relocation measures against those who lose their base of livelihood due to the instant project, the Korea Land Corporation decided to specially supply the instant land for detached houses to be developed within the instant project district (hereinafter “instant land for migrants”). Accordingly, Nonparty 1 and Nonparty 2, who resided within the instant project district, entered into a sales contract with the Korea Land Corporation on March 16, 2007, to purchase (number 1 omitted) approximately KRW 264 square meters and KRW 40,130,000 among the instant land for migrants, and ② Nonparty 2 agreed to purchase (number 2 omitted) approximately KRW 260 square meters and KRW 389,920,00 among the said land for the said migrants (hereinafter “instant housing site”), and each of the said sales contracts was concluded between the Korea Land Corporation and the Korea Land Corporation (hereinafter “instant sales contract”).

C. The Korea Land Corporation calculated the sales price based on the unit price calculated by applying the gap rate by individual parcel to the unit price per square meter in accordance with the established rules on the establishment and implementation of relocation measures (hereinafter “established rules on relocation measures”), which are internal rules at the time of entering into each of the instant sales contracts (the relevant provisions are as follows) (Subject to each of the instant sales contracts, the entire area is not more than 265 square meters).

In principle, the scale of supply of multi-resident housing sites under Article 16 (Scale of Supply) of the established rules on the establishment and implementation of relocation measures included in the main text shall be 165 square meters or 265 square meters per parcel: Provided, That the same shall not apply where it is inevitable in consideration of the conditions of the relevant project district, such as conditions to be demarcated, land use plans, efficiency of land use, etc., the real estate market trends in the relevant region, etc., the unit price of supply of multi-resident housing sites may be calculated in accordance with the following standards:

Standard for calculation of the unit price of supply of the housing site for migrants 2 attached Table 1] 1. [total project cost (excluding relocation measures expenses; hereinafter the same shall apply) - basic living facilities installation cost] 2. [total project cost - basic living facilities installation cost] + basic living facilities installation cost 】 (area of public facilities - area of existing public facilities) for consideration for an area subject to supply of public facilities;

D. After that, Plaintiff 1 entered into a contract on June 12, 2007 with Nonparty 1 and Plaintiff 2 with Nonparty 2 on April 3, 2008 to succeed to all rights and obligations as purchaser under each of the instant sales contract with Nonparty 2 with the consent of the Korea Land Corporation. Meanwhile, the Korea Land Corporation was merged with the Korea Land Corporation on October 1, 2009 and became the Defendant (hereinafter collectively referred to as the “Defendant”).

E. After the creation of a housing site, Plaintiff 1 settled the actual selling area of the housing site with 263.2 square meters, and accordingly, on March 19, 2009, the Defendant paid 398,129,29,290 won by deducting 78,200 won of the sales price calculated according to the above actual selling area, which was calculated by deducting 398,917,490 won for advance payment, from the total of 398,29,290 won. Plaintiff 2 maintained the sales area as is 260 square meters even after the creation of the housing site, and until November 6, 2009, the Defendant paid 389,923,290 won for delay and advance payment (damage 6,043,720 won for delay damages, and 6,040,430 won for advance payment).

[Ground of recognition] Facts without dispute, Gap evidence 1 through 4, Gap evidence 6, 7, Eul evidence 10, 13, and 33, the purport of the whole pleadings

2. The plaintiffs' assertion

In accordance with Article 78(4) of the former Act on Acquisition of and Compensation for Land, etc. for Public Works Projects (amended by Act No. 8665 of Oct. 17, 2007; hereinafter “former Public Works Act”), the Defendant calculated the sales price of each of the instant sales contracts without deducting the basic cost of living facilities from the Defendant himself/herself in supplying housing sites to a person subject to relocation measures, and thereby, the Plaintiffs paid the sales price that includes the cost of the basic living facilities. However, among each of the sales contracts in this case, the part that included the cost of the basic living facilities in the sales price is invalid because it violates the above provision, which is a mandatory law. Accordingly, the Defendant gains profits equivalent to the cost of the basic living facilities and thereby causes damages equivalent to the same amount to the Plaintiffs. Accordingly, the Defendant is obligated to return unjust enrichment equivalent to the amount stated in each of the claims to the Plaintiffs.

3. Return of unjust enrichment:

A. Basic Law (see Supreme Court en banc Decision 2007Da63089, 63096 Decided June 23, 2011)

1) Article 78(1) of the former Public Works Act provides that a project operator’s duty to establish and implement relocation measures, and Article 40(2) of the Enforcement Decree of the same Act (amended by Presidential Decree No. 20722, Feb. 29, 2008; hereinafter “former Enforcement Decree of the Public Works Act”) provides that “Measures for relocation shall be established and implemented where the person who wishes to move among those subject to relocation measures is at least 10 persons, except in extenuating circumstances as prescribed by the Ordinance of the Ministry of Construction and Transportation: Provided, That where a project operator supplies a housing site or house (including cases where the housing is supplied through a project operator’s arrangement) to those subject to relocation measures pursuant to relevant Acts and subordinate statutes, such as the Housing Site Development Promotion Act and the Housing Act, the relocation measures shall be deemed to have been established and implemented.” Meanwhile, Article 78(4) main sentence of the former Public Works Act provides that “The details of relocation measures shall include road, water supply facilities, drainage facilities, and other basic facilities in the relocation area.”

In full view of the above provisions, it is reasonable to view that a project operator may supply a housing site or house (hereinafter “special supply”) to a person subject to relocation measures pursuant to the proviso of Article 40(2) of the former Enforcement Decree of the Public Works Act as a means of relocation measures that a project operator may choose pursuant to the delegation of Article 78(1) of the former Public Works Act. In the case of special supply, it is reasonable to view that a project operator should install basic living facilities under Article 78(4) of the same Act at the cost of the project operator to provide the person subject to relocation measures, as in the case of providing a settlement site, and that the housing site or house market price acquired by the person subject to relocation measures through special supply is given an opportunity or possibility to obtain profits from the market price by considering

The purpose of the former Public Works Act is to promote the promotion of public welfare and the appropriate protection of property rights through the efficient implementation of public works by prescribing matters concerning compensation for losses incurred by the acquisition or use of land, etc. necessary for public works through consultation or expropriation. Measures for resettlement under the same Act is a system prepared to restore the previous living conditions to those subject to relocation measures who lose their base of life due to the provision of land, etc. necessary for the implementation of public works and ensure a decent life at the same time. Thus, the main text of Article 78(4) of the former Public Works Act, which provides for the duty to establish and implement relocation measures, is a mandatory law that is not only Article 78(1) of the former Public Works Act, but also Article 78(4) of the same Act, which provides for the contents

Furthermore, the purpose of Article 78(4) of the former Public Works Act is to provide the person subject to relocation measures with a basis of living. Thus, the term "basic living facilities according to the relevant regional conditions, such as roads, water supply facilities, drainage facilities, and other public facilities" under the said provision means roads, water supply and drainage facilities, electric facilities, telecommunications facilities, gas facilities, or district heating facilities, which are installed by a project operator who implements a housing construction project or a housing site development project under the relevant statutes, such as Article 23 of the Housing Act

Therefore, if a person subject to relocation measures pays to a project implementer the basic cost of living facilities by including the cost of the basic living facilities as stipulated in Article 78(4) of the former Public Works Act in a special supply contract for housing or housing entered into between a person subject to relocation measures and a project implementer, the portion of the special supply contract containing the cost of the basic living facilities in the sale price is null and void in violation of Article 78(4) of the former Public Works Act, which is a mandatory law, and ultimately, the project implementer obtains a benefit equivalent to the cost of the basic living facilities without any legal cause and thereby causes damages equivalent to the same amount. Therefore, the project implementer is obligated to return the amount to the person subject to relocation measures for unjust enrichment.

2) Meanwhile, if a party to a contract transfers a position as a party to a contract comprehensively to a third party upon entering into a three-dimensional contract between the other party and a third party or with the consent of the other party, the third party who has taken over the status as a party to the contract succeeds to the status of the transferor’s contractual position, thereby having all the bonds

B. Determination

In light of the facts acknowledged above and the above legal principles, since the plaintiffs comprehensively acquired the status of purchaser under the contract for sale in this case with the defendant's consent, the plaintiffs were comprehensively transferred to the plaintiff's claim for return of unjust enrichment arising in relation to each contract for sale in this case. However, since the sale price stipulated in each contract for sale in this case includes the cost of basic living facilities as stipulated in Article 78 (4) of the former Public Works Act, if the plaintiffs were to pay the defendant the cost of basic living facilities to the defendant, the part is null and void in violation of the above provision, which is a mandatory law, and the defendant, who is the project operator, obtains profits equivalent to the cost of basic living facilities, and thereby causes damages equivalent to the same amount, the defendant is obligated to return that amount to the plaintiffs with unjust enrichment.

4. Scope of unjust gains;

(a) Method of calculating the amount of unjust gains;

1) As seen earlier, the Defendant calculated the sales price of the portion of less than 265 square meters out of the instant multi-resident’s housing site by comparing the amount calculated by deducting the cost of basic living facilities according to the Defendant’s calculation method based on the total project cost - the cost of relocation measures) and the amount equivalent to 80 percent of the cost of housing site development. As such, the amount of unjust enrichment that the Defendant is obligated to return to the Plaintiffs should first be calculated on the basis of the cost of housing site development [the amount of unjust enrichment that the Defendant should return to the Plaintiffs should be calculated on the basis of the cost of legitimate sales in each of the instant sales contracts [the amount of unjust enrichment that the Defendant calculated on the basis of the cost of housing site development - the cost of housing site development - the cost of basic living facilities ± the cost of housing site development x the sales price at the time of each of the instant sales contracts

2) On the other hand, the cost of the basic living facilities is comprised of the sum of the site cost [1st cost required for the purchase of the site for the project district, x (the installation area of basic living facilities ¡Àtotal project area)] and 2nd cost, 3st cost, direct personnel cost, sales cost and management cost, capital cost and other cost, which corresponds to the above cost of the basic living facilities and the cost of the creation.

(b) Calculation of costs of installing basic living facilities;

1) The cost of housing site preparation and the project area

Comprehensively taking account of the overall purport of the arguments in Eul evidence Nos. 2 through 6, Eul evidence Nos. 10, 27, and 33, the fact that the total business area of the business in this case was 9,307,148 square meters (where there are several changes in the area after the time of designation of the first planned housing site development district, based on the area around May 17, 2005, the total project cost was estimated) of which is 3,545,124 square meters. The total project cost of the business in this case is estimated as follows as of May 17, 2005, and the total project cost of the project in this case, except for the relocation measures expenses that cannot be considered as the expenses for the creation of housing lots from total project cost, the total project cost in this case is recognized as 7,859,639,50,000 won (=7,968,645,621,000,000 won).

3,432,513,00 direct labor cost of 127,023,203,00,000 direct labor cost of 1.93% relocation measures cost of 1.93% relocation measures cost of 209,206,121,00 indirect labor cost of 364,94,374,000 land cost, development cost of 5.44% capital cost of 770,058,346,000 direct labor cost of 5.69% of the total labor cost of 5.69% of the total labor cost of 3,149,000,000 direct labor cost of 3,00,000,000,000,000,000,000,000,000,000,000,000,000,000,0000,0000,005,0686,06,05,06,0

(ii)the cost of sites for basic facilities;

(a)the area where basic living facilities are installed;

The facts that the installation area of basic living facilities, which can be recognized as arterial facilities among the project districts of this case, is a total of 1,706,629 square meters in the following table, are not disputed between the parties, or are recognized by considering the overall purport of the pleadings as a whole in the statement in subparagraph 10, No. 12-1, No. 15, B-1, No. 16, 28, and No. 29-1 and No. 2.

Water supply sites 27,291 partially recognized 27,291 of the 3rd square 2 square 2 square 27,681, part recognized as part of the 3rd 3rd 2 square 2 square 27,681, which are located in the main body, shall be recognized as 35,98,000 total 7 sewage pumping stations 2,40,629 square 1,706,629 square 2,629 square 2,00 total recognition of the 5rd 7rd 6 sewage treatment stations in full recognized as 35,998.

B) Determination by item

(a) Roads:

Based on the classification of roads pursuant to Article 9 of the Regulations on the Determination, Structure, and Standards for Installation of Urban or Gun Planning Facilities (Ordinance of the Ministry of Land, Infrastructure and Transport) with respect to the area of the portion of roads, the defendant asserts that ① roads around the road, main roads, auxiliary roads, aggregate roads, and national roads with a width of at least eight meters are not basic living facilities, but roads for a period, so the area should be excluded. ② Preliminary assertion is that at least a main road among the highways and the general roads, the main roads and auxiliary roads should not be a main road. In particular, the defendant asserts that the main roads among the main roads cannot be regarded as a main road corresponding to basic living facilities as a metropolitan road.

In light of the provisions of relevant Acts and subordinate statutes, including Articles 2, 21, and 23 of the former Housing Act (amended by Act No. 9405, Feb. 3, 2009; hereinafter the same shall apply), a road which is an arterial facility installed under a housing construction project or a housing site development project to which the former Housing Act applies is responsible for connecting the entrance of a housing complex located outside the project district and other roads located outside the project district, and is also an essential facility for accomplishing the functions of the housing complex, etc. and for passage of residents regardless of length or width. A project undertaker is obligated to install the roads in accordance with the former Housing Act and subordinate statutes and the housing site development project plan or the housing site development project plan based thereon. 13, 201; 203, the former Housing Act and subordinate statutes and the Act and subordinate statutes and subordinate statutes are also established within the said housing complex and provided to persons subject to relocation measures within the said housing site development project or housing site development project within the said project district, and 13, 2016, 3, 3, 16, 2, 2, 3, 2, and 3, 3, 1, 2,2, 3.

However, comprehensively taking account of the overall purport of the pleadings in the written evidence Nos. 10 and 15, it is recognized that the entire area of the road area of 1,475,882 square meters in the instant project district includes the area of 19,900 square meters (excluding the area corresponding to the plaza considered in the front and rear), and the area of 32,844 square meters (excluding the area of a river bridge) of the Gangwon-Seoul Highway. The area of a road corresponding to the basic living facilities among the roads installed in the instant project district in the instant project district is 1,423,138 square meters (=1,475,882 square meters - 19,900 square meters - 32,844 square meters). Therefore, the Defendant’s above assertion is reasonable within the scope of recognition.

(2) squaress:

(A) Comprehensively taking account of the overall purport of the pleadings in the written evidence Nos. 10, 12-1, and 16 of Eul, the traffic squares No. 1 (excluding 1,942 square meters, river bridge area), 2 traffic squares (excluding 306,920 square meters, river bridge area), 3 traffic squares (excluding 15,349 square meters) and 334,211 square meters in the instant project district. Among them, the traffic squares No. 2 can be recognized as being a traffic plaza attached to the road. The traffic squares can be deemed as a road facility, and it is included in the basic living facility. However, the traffic squares No. 2 is not deemed as a basic living facility. Accordingly, the traffic squares No. 1 and the traffic squares No. 37,291 square meters are recognized as a basic living facility.

(B) The plaintiffs asserted that all general squares, other than traffic squares, should be included in the basic living facilities. However, each of the above evidences alone is insufficient to recognize that the general squares constitutes the basic living facilities, which are arterial facilities, and there is no other evidence to acknowledge this otherwise, the above assertion is without merit

(3) Part of the water site and the pressurization.

The Defendant asserts to the effect that the entire site for water supply and the part of 76,760 square meters in the district of this case among the voltages does not constitute a basic living facility as metropolitan water supply facilities for supplying raw water drawn from the arms to each district of the Seoul Metropolitan area. However, in full view of the overall purport of the pleadings in each part of the evidence Nos. 10, 16, 28, and evidence Nos. 29-1, and 29-2, it is reasonable to view the above water supply site and the part of the pressure 76,760 square meters in the above water supply facility is not a metropolitan water supply facility regardless of the project district of this case, but a facility used to supply water within the project district of this case. Therefore, it is reasonable to deem that the above water supply site and the pressure tension are an arterial facility. Therefore,

(d) drainage stations, sewage treatment stations, and sewage treatment pumps;

The defendant asserts that each of the above facilities constitutes a water supply and sewerage-related facility, but it is not an arterial facility but an essential infrastructure that constitutes a water supply and sewerage facility, and therefore it does not constitute a basic living facility.

However, even if each of the above facilities installed within the project district of this case falls under a key facility as alleged by the defendant, it is not reasonable in light of the purport of the former Public Works Act stipulating that the person subject to relocation measures should not bear the cost of arterial facilities in order to maintain the living conditions of the previous facilities in the housing site development zone if the project operator installs key facilities within the housing site development zone instead of installing key facilities and using key facilities outside the housing site (see Supreme Court Decision 2012Da37374, 37381, Jan. 16, 2014). Thus, it is reasonable to view that the area of each of the above facilities is included in the area of the basic facilities installed, so the above argument by the defendant is rejected.

(5) Power transformations, gas supply facilities and integrated energy supply facilities;

The plaintiffs asserts that the land should be included in the area where the basic living facilities are installed, since the transformation stations, gas supply facilities, and integrated energy supply facilities fall under the basic living facilities.

However, in a case where a project proprietor supplied a site for electricity, gas, or collective energy supply facilities to a person who supplies electricity, gas, or heating in the relevant area for at least the cost of housing site development, the site cost cannot be deemed to have been paid for the sale price, and thus, it does not include the cost of the site in the cost of basic living facilities (see Supreme Court Decision 2012Da37374, 37381, Jan. 16, 2014), and Article 6, 24, 25, and 26-1, and 26-2, the whole argument of each of the above sites in consideration of the purport of each of the arguments is acknowledged. Since it is recognized that the Defendant supplied each of the above sites to the Korea Electric Power Corporation, the Korea Gas Corporation, and the Korea District Heating Corporation, respectively, with the cost of housing site development at least the cost of housing site development in the instant project district, it is therefore difficult to view that each of the above sites is included in the area of the basic living facilities.

(6) Railroad facilities, rivers, reservoirs, and automatic waste collection facilities;

Although the plaintiffs asserted that the area of each of the above parts should be included in the installation area of basic living facilities, it is difficult to regard them as basic living facilities, and even in the case of rivers, storage sites, and waste automatic collection facilities, it is difficult to regard them as falling under the basic living facilities for which the project implementer bears the duty of installation, and there is no other evidence to acknowledge them. Therefore, this part of the plaintiffs' assertion is without merit.

C) Calculation of land costs

Ultimately, the land cost for basic living facilities due to the instant project is a total of KRW 577,424,456,406 (i.e., total land cost of KRW 3,149,000,090,000 x basic living facilities area of KRW 1,706,629 square meters ± total business area of KRW 9,307,148 square meters, but less than KRW 1,56,406 (hereinafter the same).

(iii) cost of creating basic living facilities;

A) Comprehensively taking account of the overall purport of the arguments in the evidence Nos. 2 through 4, Nos. 10, 15, 16, 20, 22, and 23, the amount recognized as the cost of creating basic living facilities out of the total cost of the instant project is the aggregate of KRW 1,002, 964, 292,797, as seen below.

(1) Full recognition of the installation costs: 2 to 4, Nos. 8 through 15

(2) Recognition of only a part of the installation costs: ① Serial 1,6,16, or 18 [Recognition to the extent that the ratio of the area in which the basic living facilities are installed (the area in which the basic living facilities are installed 1,706,629 square meters ± the total business area 9,307,148 square meters)]; ② 5, and 7 [Recognition to the ratio of roads corresponding to the basic living facilities (the area in which the basic living facilities are installed ± the ratio of roads 1,423,138 square meters ± the total road area 1,475,82 square meters)];

Part 33,612,373,572 (ju 1) of non-approval of part 33,472 of non-approval of 13,343,00,30 of non-approval of 23,895,000 of water supply capacity of 4,895,000 and 63,058,925,204 (ju 2) of non-approval of part 668,607,607,607,60,6067,60,60,607, 607, 607, 607, 607, 607, 607, 607, 607, 607, 607, 605, 607, 607, 607, 605, 2016, 106, 2016, 106, 2001, 766,

Note 1) 3,612,373,572

Note 2) 63,058,925,204

Note 3) 3,404,952,183

Note 4) 15,526,558,407

Note 5) 5,501,026,737

Note 6) 1,246,716,026

Notes 1,378,740,668

B) Determination by item

(a) Roads and packaging fixtures, street lamps;

The defendant asserts that the expenses for road, packing, and streetlights should be recognized to the extent equivalent to the ratio of the size of the road corresponding to the basic living facilities among the roads in the instant project district for the same reasons as alleged in subparagraph 2 (b) (1).

The facts that the roads in the project district of this case include a light highway which cannot be viewed as a basic living facility and a light railer highway among the roads in the project district of this case are as seen earlier. Therefore, the expenses for the roads, packing, and streetlights for each of the above motorways shall be excluded from the expenses for creating basic living facilities, but the expenses for the road, packing, and streetlights shall be calculated by the amount equivalent to the ratio of the remaining area, excluding the area of the said motorway, among the total expenses for the roads in the project district

(b) excellent pipes, wastewater pipes, water supply pipes, underground lanes, tunnels, bridges, bridges;

The defendant asserts that the construction cost of each of the above facilities should be recognized as equal to the ratio of the basic living facilities to the total project area. However, in the case of excellent public water, sewage water and water supply pipes, all of the expenses related to water supply and sewerage facilities, which are basic living facilities, constitute the expenses related to water supply and sewerage facilities, and in full view of the whole purport of pleadings in the statement of evidence Nos. 10 and 22, it can be recognized that all of the underground teas, tunnels, bridges, bridges, and bridges are installed on roads, which are not national expressways, and thus, the defendant's above assertion is not accepted.

(iii) earth and sand, military units, survey and design, final and conclusive survey and supplementary unit costs;

In full view of the purport of the entire arguments, it is reasonable to deem that each of the above costs was used for construction of the entire project of this case. As such, it is reasonable to view that the part of the above costs amounting to the ratio of the “establishment area/total business area of basic living facilities” as the cost of

In regard to this, the defendant asserts that the incidental work cost, confirmation survey cost, and incidental cost are irrelevant to the cost of construction of basic living facilities, but it is difficult to believe that the entry of Eul No. 19, which seems consistent with this, is difficult, and there is no other evidence to prove otherwise.

(d)Expenses related to the metropolitan transport facilities (Yuk-Feyang-Fed Roads, identification line charges, and other costs for the disposal of metropolitan transport);

The plaintiffs asserts that the common morals-Mak Road charges, identification line charges, and other metropolitan transportation processing costs should also be included in the cost of creating the basic living facilities.

However, comprehensively taking account of the legislative purport and contents of relevant provisions, such as Articles 2 and 7 of the former Special Act on the Management of Intercity Transport in Metropolitan Areas (amended by Act No. 8251, Jan. 19, 2007; hereinafter “former Intercity Transport Act”) and Article 9 of the former Enforcement Decree of the Intercity Transport Act (amended by Presidential Decree No. 20021, Apr. 20, 2007); the cost incurred in the improvement and construction of intercity transport facilities in a large-scale development project in a metropolitan area to increase the value of a housing site and a house in a metropolitan area due to the cost incurred in the construction and improvement of intercity transport facilities; thus, a person who is supplied with a housing site or a house cannot be deemed as falling under the cost of establishing a basic living facility; thus, (see, e.g., Supreme Court Decisions 2012Da59268, 69275, 59282, Apr. 17, 2013).

(v)a structure hole, a river hole, a reservoir hole, a border river wharf, a waste transport pipe, and a waste incineration station;

Although the plaintiffs asserted that the expenses required for the installation of each of the above facilities should also be included in the cost of creating the basic living facilities, it is difficult to see that they fall under the basic living facilities as examined earlier in the case of a river and a reservoir, and it is insufficient to recognize that each of the above facilities falls under the basic living facilities only on the ground of the statement in the certificate No. 4, and there is no other evidence to recognize it. Accordingly, this part of the plaintiffs' assertion is without merit.

(iv) direct personnel expenses, etc. for the basic living facilities;

A) Direct labor cost included in the total project cost of the instant project is 1.93% of the total amount of site and development cost. Sales and management cost is 5.44% of the total amount of site and development cost, and capital cost is 5.69% of the total amount of net input cost, and other expenses are 0.24% of the total amount of site and development cost, and the total amount of direct labor cost is 0.24% of the total amount of the total amount of the total amount of net input cost. As seen earlier, each of the above expenses includes expenses accompanied by or contributed to the installation of basic living facilities. Therefore, the part related to the cost of basic living facilities and development cost of each of the above expenses must be included in the calculation of the cost of basic living facilities (see Supreme Court Decisions 2012Da47272, Nov. 28, 2013; 2012Da83902, Dec. 26, 2013, etc.).

In this regard, the defendant asserts that the capital cost is unrelated to the installation cost of basic living facilities, but the capital cost is borne by the defendant in relation to the capital raised and operated by the defendant for the execution of the project in this case. Since some of the raised capital is invested in the site cost and creation cost of basic living facilities, it is reasonable to view that the capital cost also includes the basic living facilities installation cost.

B) Of the direct personnel expenses, sales and management expenses, capital expenses, and other expenses for the instant project, the part relating to the site cost and creation cost of the basic living facilities is calculated as follows:

(1) Direct labor cost = (the site cost for basic living facilities + creation cost)x 1.93% = Note 8) 30,501,502,859 won

(2) Sales and management expenses = (the cost of the site for the basic living facilities + the cost of creation + direct personnel expenses) = 5.4% = Note 9) 87,632,429,712

(3) Capital cost = Total capital costx (basic facility site cost + creation cost + direct personnel cost) ¡À (total site cost + creation cost + direct personnel cost) = 184,910,601,793 won per week)

(4) Other expenses = (basic facility site cost + creation cost + direct personnel expenses) = 11 per week) 3,866,136,604 won

(5) Aggregate: 306,910,670,968 won;

C. Calculation of unjust enrichment by Plaintiff

(a) A reasonable unit price for sale;

The reasonable unit price to be paid by the Plaintiffs to the Defendant according to each sales contract of this case is KRW 1,684,663 per square meter (=(the unit price for housing site development is KRW 7,859,639,50,000 - KRW 12) 1,887,29,420,171) ± the unit price for housing site development ± the unit price for housing site supply 3,545,124 square meters).

2) The lawful sale price reflecting the gap rate

A) The fact that the rules on the relocation measures stipulate that the supply price of each of the instant housing sites may be differentiated by lots of migrants is as seen earlier. In full view of the purport of the entire pleadings in the written evidence Nos. 6, 9, and 35, the Defendant set the supply unit price of each of the instant housing sites at KRW 1,691,804 per square meter at the time of each of the instant sales contracts, and determined the sale price by applying the gap rate (0.951 for the land that was sold by Plaintiff 1 and 0.941 for the land that was sold by Plaintiff 2) taking into account the individual circumstances of each of the instant housing sites. However, the specific method of calculating the sale price by reflecting the gap rate at the time is recognized as “the unit price of the housing site supplied by migrants (1,691,804 won) x x 145,392 square meters (the total area subject to the application of the gap) / 154,341 square meters (the total area of the housing site).”

B) However, in cases where a business entity individually determines the sales price of a resettled housing site by applying a gap within the scope of discretion, it may be deemed that the development cost of the entire resettled housing site was differentiatedly allocated to each resettled housing site in accordance with the conditions of the location. Therefore, when calculating the development cost and basic living facilities installation cost of each resettled housing site and the legitimate sales price based thereon, the relevant gap shall be calculated by reflecting the relevant gap (see Supreme Court Decision 2014Da6572, Aug. 20, 2014). In such a case, it is reasonable that the business entity should take the same method as the initial business entity reflects the difference (the Defendant asserts that the sales price of the pre-sale housing site at the time of each of the instant sales contract in this case should reflect the difference by dividing the unit price of supply of the pre-sale housing site at the same time by the rate of 1,691,804 won per the unit selling price, but it shall not be accepted).

C) Therefore, the aforementioned legitimate unit sale price (1,684,663 won/m2) is calculated by calculating the legitimate unit sale price reflecting the gap rates for each Plaintiff by the Plaintiff as follows.

(1) Plaintiff 1

0.951x gap rate of the legitimate unit price for sale in lots (1,684,663 square meters) x 263.2 square meters x 145,392 square meters /154,341 square meters x 397,226,890 won, which was settled after the creation of housing sites.

(2) Plaintiff 2

0.941x gap rate of 0.941x 260 square metersx 145,392 square meters/154,341 square meters = 388,271,228 won

3) The amount of unjust enrichment by the plaintiff

A) Plaintiff 1

(1) Inasmuch as the lawful sale price of KRW 397,226,890 is less than the existing sale price of KRW 398,917,490, which was adjusted for the area after the creation of a housing site, the said Plaintiff’s unjust enrichment to be returned from the Defendant is the principal (=398,917,490 won - 397,226,890 won).

(2) Meanwhile, as seen earlier, the fact that Plaintiff 1 received advance payment of KRW 788,200 while paying the sale price is identical to the fact that Plaintiff 1 received advance payment of KRW 3,340 (= KRW 788,200x1,690,600/398,917,490). Since the said amount was discounted due to the principal of the said unjust enrichment, Plaintiff 1’s deduction from the principal of the said unjust enrichment is KRW 1,687,260.

B) Plaintiff 2

(1) Inasmuch as the lawful sale price of KRW 388,271,228 is less than the sale price of KRW 389,920,00,00, the amount of unjust enrichment that the said Plaintiff is obligated to return from the Defendant is KRW 1,648,772 (i.e., KRW 389,920,000 - 388,271,228).

(2) On the other hand, if Plaintiff 2 pays the sale price and pays the delay damages and the advance payment delay damages, the fact that Plaintiff 2 paid 290 won is as seen earlier. Of these, 1 won (=290 won x 1,648,72 won/389,920,000 won) is the amount additionally paid due to the principal of the above unjust enrichment, and thus, it is KRW 1,648,773 if it is added to the principal of the above unjust enrichment.

4) Sub-committee

Therefore, the defendant is obligated to pay the legal interest or delay damages calculated at the rate of 20% per annum as stipulated in the Civil Act from November 25, 2010, when it is evident that it is the delivery date of a copy of the complaint of this case to the plaintiff 1,687,260, and to the plaintiff 2, and each of them, from November 15, 2010 (see Supreme Court Decision 2012Da84233, Jan. 23, 2014; Supreme Court Decision 2012Da84233, Nov. 25, 2014; Supreme Court Decision 5% per annum as stipulated in the Civil Act until November 25, 2014, which is the date of the return of unjust enrichment, to the plaintiff 1,648,73, and each of them are the delivery date of a copy of the complaint of this case (the plaintiff is a malicious beneficiary under the premise that the plaintiff is a malicious beneficiary, and there is no evidence to acknowledge that the plaintiff's payment is the beneficiary.

5. Conclusion

Therefore, the plaintiffs' claims of this case shall be accepted within the scope of each above recognition, and the remaining claims shall be dismissed for reasons. Since the judgment of the court of first instance is partially unfair with the conclusion, the part against the plaintiffs corresponding to the above order of payment among the judgment of the court of first instance shall be revoked and the defendant shall be ordered to pay the above amount, and the remaining appeals of the plaintiffs shall be dismissed for reasons. It is so decided as per Disposition.

Judges : Judges Hadro Madro (Presiding Judge)

Note 1) Total soil construction cost of KRW 183,306,00,000 x 1,706,629/9,307,148

Note 2) 65,396,00,000 total roads and packaging fixtures x 1,423,138/1,475,82

Note 3) Total appurtenant work costs of 18,569,00,000 x 1,706,629/9,307,148

Note 4) Total street lamps 16,102,00,000 x 1,423,138/1,475,882

Note 5) The total survey and design cost of KRW 30,000,000 x 1,706,629/9,307,148

Note 6) Total final survey costs of KRW 6,799,00,000 x 1,706,629/9,307,148

Note 7) Total incidental cost of KRW 7,519,00,000 x 1,706,629/9,307,148

Note 8) 30,501,502,859 = 1,580,388,749,204 won = Development cost of KRW 577,424,456,406 + Development cost of KRW 1,002,964,292,797) x 1.93%

9) 87,632,429,712 = 1,610,890,252,062 won (basic living facility site cost, development cost, 1,580,388,749,204 won + 30,501,502,859 won directly related to development cost) x5.44%

10) 184,910,601,793 = 770,058,346,00 won (total capital cost) x 1,610,890,252,062 (basic living facilities cost, creation cost, direct labor cost) ±6,708,536,293,000 won (total land cost 3,149,000,000,090 + creation cost 3,432,513,000,000 won + direct labor cost 127,023,203,003,000 won)

Note 11) 3,866,136,604 = 1,610,890,252,062 (basic living facility site cost, creation cost, and direct personnel cost) x0.24%

Note 12) 577,424,456,406 + 1,02,964,292,797 + 306,910,670,968 won