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

A. The plaintiff (Counterclaim defendant) and the defendant (Counterclaim plaintiff) Eul Co., Ltd. on 79.

A principal lawsuit and a counterclaim shall be deemed simultaneously.

Basic Facts

The plaintiff is the owner of Yongsan-gu Seoul Metropolitan Government D major 337 square meters and a detached house with the third floor above that ground (hereinafter referred to as the "house of this case").

Defendant B (hereinafter “Defendant B”) is a company engaged in the tesenal business, etc., and Defendant C is an individual entrepreneur who engages in the original agriculture, etc. under the trade name of “F.”

On August 22, 2016, the Plaintiff drafted a contract for construction work (hereinafter “contract for construction work in this case”) between the Defendants and the Defendants by setting the construction cost of KRW 327,852,00 (excluding value added tax), and the construction period from June 27, 2016 to September 30, 2016 (hereinafter “contract for construction work in this case”).

The Plaintiff paid KRW 202,40,000, and KRW 29,940,800 each to Defendant C on September 19, 2016, respectively, from July 22, 2016 to September 19, 2016, respectively, as down payment and intermediate payment under the instant contract.

The Defendants, around October 28, 2016, notified the Plaintiff of the completion of the instant construction work and requested the Plaintiff to take over the instant construction site and pay the remainder of the construction work.

Article 6 of the contract of this case provides that the payment of the balance of construction cost shall be KRW 65,570,700 within five days after completion of the construction.

On December 30, 2016, the Plaintiff: (a) certified mail proving the contents to the Defendants, “Many defects have occurred in the construction of a garden, swimming pool, etc. during the instant construction; (b) such defects are serious defects in which repair is impossible; and (c) a full-scale removal and reconstruction is required; and (d) the Defendants’ return of the already paid construction cost and removal and reconstruction costs due to the defects on the grounds that the Defendants had issued an excessive advance payment of the construction cost by the method of covering the unit price, etc. of the instant construction