1. The Defendant (Counterclaim Plaintiff) paid KRW 6,594,142 to the Plaintiff (Counterclaim Defendant) and its related amount from October 1, 2014 to December 5, 2017.

A principal lawsuit and a counterclaim shall be deemed simultaneously.

1. Basic facts

A. On June 27, 2014, the Plaintiff entered into a contract with the Defendant for the construction of an apartment building of 73 households, officetels 14 households, and a building with three households located in Busan-gun, Busan-gun (hereinafter “instant building”) with the construction cost of KRW 165 million for the production and construction of a household, such as the Jinck (hereinafter “instant construction”) as the construction cost, and completed the said construction around September 2014. Around that time, the Plaintiff received KRW 165 million for the construction cost from the Defendant.

B. Meanwhile, on September 2014, the Plaintiff issued a written claim to the Defendant for additional construction costs of KRW 19.1 million, after completing the construction work, such as the extension of the stalthy of the stalthy, the office attached to the office house, and the stalthy construction (hereinafter “instant additional construction work”).

[Grounds for recognition] The descriptions of evidence Nos. 1 and 2, and the purport of the whole pleadings

2. As to the main claim

A. The Plaintiff asserted that the Plaintiff is obligated to pay the Plaintiff the additional construction cost of KRW 19.1 million and its delay damages, since the Plaintiff agreed to perform the instant additional construction work with the Defendant and completed the additional construction work in an amount equivalent to KRW 19.1 million around the end of September 2014.

In this regard, the defendant did not agree with the plaintiff on the additional construction of this case, and even if it is not so, 1,30,000 won should be deducted from the additional construction cost, as office attached houses and 1,300,000 won are not constructed among the additional construction of this case, and 11,205,858 won should be offset against the plaintiff's claim for additional construction cost.

B. Whether to agree with the 1 additional works, the Plaintiff stated in the written claim that the Defendant’s completion of the additional works and the amount of the additional works are KRW 19.1 million and stated as “verification of the contents of the additional works” below.