A. The Plaintiff is a company engaged in electrical construction business, fire fighting business, etc.

B. On June 24, 2014, the Plaintiff received a contract from the Defendant for the construction work of electric power, fire-fighting, and information and communications (hereinafter “instant construction”) among the remodeling works for the building in the Convalescent hospital B located in the Gyeong-si, Gyeonggi-do (hereinafter “instant building”) (hereinafter “instant building”), with the construction cost of KRW 94,00,000 (excluding value-added tax), and the construction period from June 24, 2014 to August 20, 2014.

C. Around that time, the Plaintiff commenced the instant construction work, and the Defendant paid the Plaintiff KRW 20,000,000 on June 25, 2014 among the construction cost of the instant case, and additionally paid KRW 60,000,000 on August 15, 2014, and KRW 4,000,000 on the Plaintiff’s labor cost for the subcontractor was paid directly by the Defendant and paid KRW 84,00,000 to the subcontractor.

The Plaintiff completed the instant construction work around September 3, 2014.

[Ground of recognition] Facts without dispute, Gap evidence Nos. 1 and 2, Gap evidence Nos. 5 through 7, Gap evidence No. 11, Eul evidence No. 1, witness C and D's testimony, the purport of the whole pleadings

2. The plaintiff's assertion

A. While the Plaintiff had been running the instant construction project, the Defendant requested to change part of the construction project to perform additional construction works, such as visual alarming installation works, and air-conditioning power installation works, which are not included in the instant construction contract, and agreed to pay the price upon the Plaintiff’s settlement of accounts at the time of completion of the instant construction project.

B. The Plaintiff’s alteration work and additional construction cost amounted to KRW 35,398,00 (=value 32,180,000 value-added tax amounting to KRW 3,218,00).

C. Therefore, the Defendant shall pay to the Plaintiff the remainder of the construction cost of KRW 54,798,00 [=103,400,000 for the main construction cost of KRW 94,000 for the main construction cost of KRW 94,400 for the main construction cost of KRW 94,400,000 for the main construction cost of KRW 35,398,000 for the additional construction cost of KRW 32,180 for the value-added tax of KRW 3,218,00 for the additional construction cost of KRW 32,18,00 for 0