A. On March 25, 2013, the Plaintiff entered into a retaining wall construction contract with the Defendant on the retaining wall construction of the 126,500,000 won (including additional tax) for the retaining wall construction of the Kimhae-si and 13 lots (hereinafter “instant factory site”). The specific construction content at the time was that, depending on the shape of each land, the retaining wall construction works include 4m, 5m, 6m, 97m in length (the height is 4m, 37m in height, 5m in height, 30m in height, 6m in height, 30m in height), and drainage pipe construction.

B. Since then, on April 26, 2013, the Defendant demanded the Plaintiff to construct the retaining wall section of 4m and 5m height at a height of 6m, and the Plaintiff entered into a modified retaining wall construction contract (hereinafter “instant retaining wall construction contract” and “the instant retaining wall construction”) with the Defendant on April 26, 2013, where the height of the retaining wall construction of the instant factory site is 6m, the length is 80m, and the cost of construction is 121,00,000,000 (including additional dues) with the exclusion of the drainage pipe construction (hereinafter “instant retaining wall construction contract,” and “the instant retaining wall construction”).

C. On the other hand, on April 10, 2013, the Plaintiff entered into a construction contract with the Defendant for construction work with construction cost of KRW 247,50,000 (including surtax) with respect to the construction work that constructs two units of a factory building in the instant factory site. On July 1, 2013, the Plaintiff entered into a modified construction contract with construction cost of KRW 280,500,000 (hereinafter “instant construction contract”).

On May 2013, the Plaintiff completed the retaining wall construction of this case, and around August 2013, the construction of this case was completed, and the Defendant obtained approval for the use of the building resulting from the construction of this case on November 5, 2013.

E. Meanwhile, the Defendant shall pay to the Plaintiff KRW 88,00,000 as the cost of retaining wall construction of KRW 121,00,000 as well as KRW 280,50,00 as the cost of retaining wall construction of KRW 401,50,000 as the cost of retaining wall construction of KRW 217,250,00 as the cost of construction work, and the remainder of KRW 305,250,00 as the cost of construction work.