A. The Plaintiff is a person who runs interior decoration and artificial fishery in the name of D, and the Defendants intended to operate the FF golf range on the fourth floor of the building located in the Goyang-dong-gu Incheon Metropolitan City E (hereinafter “instant building”).

B. On March 23, 2013, the Defendants determined the construction period of KRW 170,00,000 upon entering into the Plaintiff and the FF golf practice range interior contract (hereinafter “instant construction contract”) and entering into a contract for interior works under the said construction contract (hereinafter “instant construction work”).

As to the contract amount, the above contract states that “the class of materials shall be used for class 1, fire retardant materials shall also be used,” and Article 6(6) of the above contract states that “the contractor shall perform the above construction work by using home weather and ice materials in the operation of KSC Co., Ltd.” * the contractor shall not increase the contract amount due to increase in raw materials prices, etc.

C. Around April 25, 2013, the Plaintiff commenced the instant construction work and completed the instant construction work on or around July 10, 2013. The Defendants paid KRW 170,000,000 to the Plaintiff according to the instant construction contract.

[Ground of recognition] Facts without dispute, entry of evidence No. 1, purport of the whole pleadings

2. The assertion and judgment

A. While the Plaintiff’s assertion was underway the instant construction project, the Plaintiff changed the construction content under the instant construction contract at the request of the Defendants, or additionally carried out construction works that were not included in the construction content, and the actual cost of the construction was paid at the request of the Defendants, and the Defendants agreed to pay the construction cost under the contract.

A total of KRW 322,805,922, including the costs incurred in the additional work, was incurred. The Plaintiff claimed KRW 290,000,000 among these costs to the Defendants, but the Defendants paid KRW 120,000,000, which is an additional cost, other than the contractual construction cost, to the Defendants.