1. The judgment of the first instance, including the Plaintiff’s claim added and reduced by this court, shall be modified as follows:

1. Basic facts

A. On April 15, 2013, F Co., Ltd. (hereinafter referred to as “F Co., Ltd.”) entered into a first construction contract with the Defendant, setting the construction period from April 15, 2013 to October 15, 2014, with respect to the construction of a new apartment house on the ground of Gyeonggi-si E (hereinafter “instant building”) in Gyeonggi-gu (hereinafter “instant new construction”) (hereinafter “instant new construction”), with respect to the construction cost of KRW 710,000,000 (excluding value-added tax) and the construction period from April 15, 2013 to October 15, 2014.

B. On February 21, 2014, L entered into a second construction contract with the Defendant to modify the said first construction contract from April 15, 2013 to May 30, 2014, with respect to the instant newly constructed construction project, the construction cost of KRW 690,00,000 (excluding value-added tax) and the construction period.

C. Since then, around March 18, 2015, the Defendant declared that L will terminate the said secondary construction contract as a dispute over the payment of construction cost and the progress of construction, and the Defendant drafted a new contract with G to conclude a new contract for the instant newly-built construction project.

On May 19, 2015, G entered into a contract with the Plaintiffs on May 19, 2015 (hereinafter “instant Newly constructed works”) to subcontract the interior and interior works (hereinafter “instant Newly constructed works”) as follows:

4. Subcontractors: D (name A after the modification, hereinafter referred to as "Plaintiff A").

5. Period of construction: on July 6, 2015, from May 26, 2015, the completion date of construction works on May 26, 2015: (1) Contract amount: (1) Value of supply; (2) Purchase tax amount of KRW 6,500,000; and (3) Total of KRW 130,000,000;

4. Subcontractors: Plaintiff B.

5. Period of construction: on July 6, 2015, from May 26, 2015, the completion date of construction works on May 26, 2015: (1) The contract amount: (1) the supply price; (2) the purchase price; (3) the total of KRW 150,000,000;

D. However, the Defendant did not conclude a contract for construction due to the occurrence of a dispute over G and construction cost, and L and the Defendant again set forth the construction cost at KRW 640,000,000 for the new construction work in the instant case around June 11, 2015.