1. The judgment of the court of first instance is modified as follows.

All of the plaintiffs' claims are dismissed.

2. The total cost of the lawsuit.

1. The reasoning for this part of the basic facts is as follows, except for the addition or modification as follows, and therefore, it is identical to the corresponding part of the judgment of the court of first instance. Thus, this part is cited by the main sentence of Article 420 of the Civil Procedure

The following information shall be added to the fourth written judgment of the court of first instance.

SECTION E: Implementation of the Construction Contract

4. Persons working at construction sites;

(c) No two construction supervisor may waive, increase, or decrease the other party’s obligations and responsibilities without the approval of the contracting officer.

Part 4 of the judgment of the court of first instance is changed to "other".

Part 5 of the first instance judgment, Part 1 of the first instance judgment, "1," shall be added to "102."

2. The grounds for this part of the allegations by the parties are as stated in the corresponding part of the judgment of the first instance, except for the addition or modification as follows. Thus, this part of the allegations by the parties are cited by the main sentence of Article 420 of the Civil Procedure Act.

On the 5th page of the first instance judgment, “Plaintiff A” is added to “A separate from the construction change contract dated March 26, 2015.”

In the first instance judgment, the Plaintiffs of KRW 4,990, 149,379 were changed to “5,880,57,000” in Part 5 of the first instance judgment.

Part 5 of the first instance judgment is replaced by "1,821,80,375 won" in Part 9 as "1,823,60,380 won".

The 5th sentence of the first instance judgment: (a) KRW 4,058,756,625 = 5,880,557,00 won - KRW 1,821,80,375 won - KRW 3,166,548,99 won = 4,990,149, 379 - 1,823,60,380,380 won in the first instance judgment. The 5th sentence of the first instance judgment is replaced by “3,478,756,625” as “2,58,548,999”.

3. Determination on the claim for construction price

A. The Plaintiffs seeking the payment of additional construction cost claims on the premise that there was an agreement between the Plaintiff A and the Defendant on the design change and additional construction, separate from the construction cost claims arising from the contract for the change of construction work made on March 26, 2015, and thus, the Plaintiffs seeking the payment of additional construction cost claims on the premise that there was an agreement between the Plaintiff A and the Defendant on the design change and additional construction.