2. The costs of lawsuit are assessed against the plaintiffs.

A. On April 15, 2015, the Plaintiffs purchased KRW 440,67 million from the Defendant-owned Seoul Dongdaemun-gu Seoul Metropolitan Government D large 13 square meters and multi-household housing owned by the Defendant (hereinafter “instant building”). The down payment of KRW 15,00,000 on the day of the contract, intermediate payment of KRW 50,000,000 shall be paid on May 29, 2015, and the remainder of KRW 375,000,000 shall be paid on June 30, 2015, and the payment of KRW 158,00,000 out of the remainder shall be deemed to succeed to the obligation to return the lease deposit of the instant building to the right-hand household (hereinafter “instant sales contract”). Meanwhile, the issue of the Defendant’s agreement that the Plaintiffs would succeed to the obligation of KRW 158,00,000,000 among the remainder on the date of the remainder shall be deemed to have been accepted (hereinafter “the right-hand household”).

B. The Plaintiffs paid to the Defendant KRW 15 million on the date of the instant sales contract, KRW 50 million on April 20, 2015, KRW 50 million on May 19, 2015, KRW 320 million on June 27, 2015, KRW 35 million on June 29, 2015, and KRW 170 million on June 29, 2015.

C. Meanwhile, among the obligations to return the lease deposit for the instant building that the Plaintiffs agreed to succeed, the obligation to return the lease deposit for the lessee E was included in the instant sales contract.

[Ground of recognition] Facts without dispute, Gap evidence Nos. 1, 2-1, 2, 3, and 5, and the purport of the whole pleadings

2. Determination on the cause of the claim

A. (1) The plaintiffs' claim for return of unjust enrichment is to pay only the remaining KRW 282 million (=40 million - 150 million - KRW 158 million) calculated by deducting the plaintiffs' total amount of the obligation to return the lease deposit they succeeded from the defendant in the sales contract of this case from the purchase price of KRW 440 million stipulated in the sales contract of this case. In fact, the plaintiffs shall pay to the defendant only the purchase price of KRW 32 million (the purchase price of KRW 440 million).