1. The plaintiff's appeal and the selective claim in the trial are dismissed, respectively.

2. The costs of the lawsuit after the appeal are filed.

1. The following facts do not conflict between the parties, or may be acknowledged by taking account of the whole purport of the pleadings as a whole in the entries in Gap evidence 1-1, 2, 2-7, 9, DaDa 1 and 2:

On August 14, 2013, the Plaintiff entered into a sales contract with Defendant B to purchase housing of 152 square meters in Mapo-gu Seoul Metropolitan Government (hereinafter referred to as “instant site”) owned by the said Defendant and of 2 floors in the ground brick slock slock slocks and roof (hereinafter referred to as “instant building”) for KRW 8.6 million (hereinafter referred to as “instant sales contract”) and paid the said Defendant KRW 8,000,000 as down payment on the date of the said contract.

B. Defendant C is a licensed real estate agent who has arranged the instant sales contract, and is a mutual aid contractor who has subscribed to the following mutual aid agreements, and the Defendant Korea Licensed Real Estate Agent Association (hereinafter “Defendant Association”) is a mutual aid contractor who performs performance guarantee to guarantee liability for damages arising from a brokerage accident of a mutual aid policyholder.

C. In light of the fence installed for the instant site and building, the shape of the land seems to be contrary to the shape of the fence, but the form of the instant site is not a square that seems to be contrary in the cadastral sense.

2. Determination as to the claim against the primary defendant

A. The plaintiff asserted as to the claim for the return of down payment due to the retroactive invalidation of a sales contract, the plaintiff was introduced the real estate of this case from the defendant C while finding a dead-type multi-household and multi-family housing site that seems to be contrary to the adequate building ratio, etc. in order to use it as a new site for a studio-type multi-household and multi-family house, and the purpose of purchasing the land of this case was to the defendant B before entering into a sales contract. The defendant B and C knew the current status and boundary line of the site of this case while they are well aware of the plaintiff, they are a dead-type square that seems to be in the shape of the site of this case in order to sell the land