(1) Upon receipt of a request from the Defendant for the instant construction project, such as the replacement of D Private Co., Ltd. in Gwangju Mine-gu, Gwangju (hereinafter “instant construction project”), the Plaintiff issued a written estimate (hereinafter “instant written estimate”) stating the construction cost of KRW 77,500,000, around July 5, 2016. The instant written estimate states the sum of the “cost for materials,” “work cost,” “work cost,” and “expenses,” for each construction item as construction cost (only including expenses are not included in some construction items). (2) On July 13, 2016, the Plaintiff and the Defendant determined the construction cost of the instant construction project as KRW 70,00,000 (excluding value-added tax), and concluded the instant contract to determine the construction cost to be modified and to determine the final construction cost after the completion of the construction project (hereinafter “the instant written estimate”).

(3) On July 20, 2016, the Plaintiff received KRW 40,000,000 in total from the Defendant and KRW 20,000,000 as construction price under the instant contract on July 28, 2016.

(4) The Plaintiff performed construction work under the instant contract from July 18, 2016 to August 2016. The Plaintiff’s construction work details are as follows: (a) the Plaintiff sent to the Defendant by mail proving the content of the construction work on September 9, 2016 (No. 8-1, hereinafter “instant specifications”).

The content of this case includes any construction work that was not included in the written estimate of this case, and was included in the written estimate of this case, but is not included in the written estimate of this case (the construction work that was not the plaintiff).

(5) On September 9, 2016, the Plaintiff sent a letter verifying the content of the instant construction payment to the Defendant, along with the instant detailed statement. On September 20, 2016, the Defendant sent a letter verifying that the construction payment requested by the Plaintiff cannot be acknowledged.

(6) The appraiser F of the first instance trial is the cost of the instant construction project performed by the Plaintiff and 98,728.