1. All appeals by the Defendants are dismissed.

2. The costs of appeal are assessed against the Defendants.

Purport of claim and appeal

1.

1. The reasons for this part of the facts of recognition are as stated in the part on “1. Basic Facts” in the judgment of the court of first instance, and thus, they are cited in accordance with the main sentence of Article 420 of the Civil Procedure Act.

2. Claim against the defendant B

A. According to the above facts finding as to the cause of the claim, Defendant B is obligated to pay the Plaintiff the remainder of KRW 889,730,100 (=the remainder of KRW 296,576,700 for the second intermediate payment of KRW 593,153,400) and the second intermediate payment of KRW 296,576,70 for the remainder of KRW 593,153,400 from October 11, 2016, the day following the due date of payment, and the remainder of KRW 593,153,40 from the date nine days after the registration of preservation of ownership of the commercial building of this case was completed, which is the date nine days after the due date of the remainder payment designated by the Plaintiff, to pay damages for delay calculated at the rate of 15% per annum, which is the overdue interest rate from December 19, 2017 to the date of full payment.

B. Although there is a major impact on the front part of the instant store in the instant case, D did not notify Defendant B of the existence of the instant columns at the time of concluding the instant sales contract.

The existence, location, area, etc. of the columns of this case are important matters that affect the conclusion of the sales contract. If Defendant B knew of the existence of the columns of this case, he did not conclude the sales contract of this case. Thus, Defendant B revoked the sales contract of this case on the ground of mistake.

In the first instance trial, Defendant B asserted “a cancellation by the network,” but this Court withdrawn.

Therefore, Defendant B is not obligated to pay the unpaid purchase price to the Plaintiff.

B. Even if it is impossible to cancel the sales contract of this case by mistake, D bears the duty to notify and explain the present state of the existence, location, area, etc. of the columns of this case to Defendant B, but it has violated its duty and has inflicted damages on Defendant B, thereby compensating for the damages incurred therefrom.