1. The Defendant’s KRW 61,255,80 for the Plaintiff and the Plaintiff’s 5% per annum from November 7, 2015 to November 29, 2016.

1. Judgment on the ground of the plaintiff's claim

A. (1) On February 17, 2015, the Defendant entered into a contract for the CCTV maintenance and repair project for transport information in Seoul Special Metropolitan City (hereinafter “Seoul Special Metropolitan City”) with the Seoul Special Metropolitan City (hereinafter “Seoul Special Metropolitan City”) to perform the CCTV maintenance and repair project for transport information in Seoul Special Metropolitan City, and to receive the price calculated according to the unit price determined in advance according to the content of the project. However, the total contract amount was KRW 177,180,500 (the total contract amount was later increased to KRW 227,180,500) with the “the contract for the CCTV maintenance and repair project for transport information in 2015” (hereinafter “the original contract”).

(2) On March 3, 2015, the Defendant: (a) performed the Plaintiff’s work under the instant prime contract; (b) determined the unit price and total contract amount to KRW 80,74,400 of the instant prime contract; and (c) concluded a blanket subcontract to pay to the Plaintiff within 7 days after the Defendant received the payment under the instant prime contract from Seoul Special Metropolitan City, which is the place of order; (c) performed the work of maintaining and repairing CCTV in Seoul B pursuant to the instant prime contract and the instant subcontract until August 3, 2015; (d) the Defendant received KRW 30,74,400 from the Plaintiff on April 28, 2015, the total contract amount to KRW 30,500,000, KRW 305,000, KRW 305,000, KRW 20,000, KRW 305,075, May 10, 2015.