1. All appeals filed by the plaintiffs are dismissed.

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

The purport of the claim and appeal is the purport of the appeal.

1. The court's explanation on this part of the basic facts is the same as the corresponding part of the judgment of the first instance (from 3, 9, to 5, 10). Thus, this part shall be quoted in accordance with the main sentence of Article 420 of the Civil Procedure Act.

2. Summary of the plaintiffs' assertion

A. Defendant D, E, and F agreed to mediate the sales contract under the instant special agreement between the Plaintiffs, the clients, and to explicitly state the instant special agreement in the terms of the sales contract, which is the broker assistant belonging to Defendant C, C, D, E, and F, claiming the amount equivalent to the down payment confiscated by Defendant C, E, and F.

Nevertheless, Defendant D, E, and F did not enter the instant special agreement in the sales contract by intention or negligence, and as a result, the Plaintiffs lost the instant sales contract in a lawsuit claiming the return of the purchase price filed against the instant seller, thereby resulting in damage to be confiscated KRW 300 million.

The above defendants' act constitutes a tort under Article 750 of the Civil Code, and even if it does not constitute a tort, it constitutes a default on the part of the clients who do not perform the important terms of the delegation contract with the broker, and Defendant C is jointly liable for the damages suffered by the plaintiffs due to the act of the affiliated broker assistant under Article 30 of the Licensed Real Estate Agents Act. Thus, Defendant C, D, E, and F are jointly liable for the damages of KRW 300 million to the plaintiffs.

B. The Defendant GG Association’s claim for mutual aid money against the Defendant GG Association is a mutual aid business entity that entered into a mutual aid agreement with the Defendant C and jointly with the Defendant C within the limit of KRW 200 million.

It is necessary to pay mutual-aid funds equivalent to the amount of damages of the plaintiffs stated in the paragraph.

C. 1 Plaintiffs filed a claim for refund of the amount equivalent to the brokerage commission against Defendant C with Defendant C paid KRW 30 million to Defendant C as the brokerage commission of the instant sales contract, and the instant sales contract was rescinded by intention or negligence on the part of Defendant C, or did not achieve the purpose of the contract.