A. On January 28, 2014, the Plaintiff entered into a service contract with the Defendant (hereinafter “instant contract”) seeking to undertake a new construction work of an apartment (hereinafter “new construction work of the instant apartment”) on the 61-4 and six parcels of Sari-si, Sari-si, Sari-si, Sari-si, Gari-si, Gari-si, which was an implementation plan for the new construction work of the Gaero District Housing Association.

B. According to the instant contract, the Plaintiff’s content of the service was “a service for authorization of an implementation plan for new construction works of the Housing Association in the Geae master area housing association” (Article 3 subparag. 2 of the General Conditions of the Technical Services Contract, which is a part of the contract), the service price was KRW 130 million when the contract was concluded, KRW 432 million, KRW 180 million when the contract was submitted, KRW 180 million when the authorization was submitted, KRW 180 million for the first progress payment at the time of the authorization, KRW 18 million for the second progress payment at the time of the authorization, and KRW 86 million for completion

(Article 8 of the General Conditions of Technical Services Contract)

On December 10, 2014, the Plaintiff entered into an additional contract with the Defendant for the incidental civil engineering (change) construction following the new construction of the Housing Association in the Geaero District. The details of the services to be performed by the Plaintiff under the said contract are “a incidental civil engineering service (revision) for the Construction of the New Construction of the Housing Association in the Gaero District Housing Association” (Article 3 subparag. 2 of the General Conditions of the Technology Services Contract). The service price is KRW 50 million when entering into a contract with the total of KRW 275 million, KRW 500,000,000,000 for the contract, KRW 1,2,500,000,000 for the contract at the end of January, March, 2015, KRW 5,500,000 for the third and fifth completed works

(Article 8. d. of the General Conditions for Technical Services)

The plaintiff is the contract of this case and C.

Preparation of documents, such as authorization of implementation plan, authorization of implementation plan, modification of development activities, and design documents necessary for modification of development activities according to the unit civil engineering (change) design service contract as stated in the paragraph.

E. On January 8, 2016, the Defendant obtained a provisional use approval for multi-family housing (multi-family housing) 14 units among the instant apartment construction works, resident welfare centers, and guard rooms as authorized by the Plaintiff’s performance of service work, and thereafter the design is modified.