1. The Defendant (Counterclaim Plaintiff) paid KRW 11,756,50 to the Plaintiff (Counterclaim Defendant) for KRW 11,756,50 and its amount from May 22, 2014 to August 19, 2015.

A principal lawsuit and counterclaim shall also be deemed a principal lawsuit and counterclaim.

1. The following facts do not conflict between the parties, or may be found in Gap evidence Nos. 1, 2, and 3, and Gap evidence Nos. 4-12, and Gap evidence Nos. 6 and 7, by integrating the whole purport of the pleadings:

On October 6, 2013, the Plaintiff engaged in the manufacturing of steel and steel structures under the trade name of “B” entered into a construction contract between the Defendant and the Defendant for the manufacturing and installation of steel frame, paint, equipment (transport separately) portion (hereinafter “instant construction”) among the construction works executed by the Defendant for the new construction of D steel frame in C, with the construction cost of KRW 122,475,00 and the construction period of KRW 122,475,00, and the construction contract from October 7, 2013 to November 25, 2013.

B. While the Plaintiff was performing the said construction, the Plaintiff was requested by the Defendant to perform the elevator additional construction (hereinafter “instant additional construction”) and issued to the Defendant a detailed statement of KRW 5,940,000, and performed that construction.

C. Around December 23, 2013, the Plaintiff left the instant construction site. The Defendant left the instant construction site, and the Plaintiff’s payment for the instant construction works and additional construction works amounting to KRW 40,00,000 on November 19, 203, KRW 40,000 on December 18, 2013, KRW 25,000,000 on March 17, 2014, and KRW 25,000,000 on March 17, 2014;

5. 14.8,00,000 Won in total.113,000,000

2. Determination on the main claim

A. The plaintiff asserted that the plaintiff is obligated to pay KRW 28,256,500,00, excluding the amount of the construction work in this case and the amount of the additional construction work in this case (value 122,475,000 value-added tax of KRW 12,247,500), which was already received by the plaintiff, as the cause of the claim in this case, and the plaintiff entered into and completed the construction contract in this case with the defendant. The defendant asserts that he is obligated to pay the plaintiff the remainder of KRW 28,256,00,00, excluding the amount of the construction work in this case (value 122,475,00 value-added tax of KRW 12,247,50, value-added tax of KRW 5940,000)

(2) As to this, the defendant asserts as follows.

When concluding the instant construction contract, the basic construction cost shall be KRW 122,475,00, but the tax invoice shall be subsequently generated.