1. The part of the judgment of the court of first instance regarding the appeal shall be revoked.

2. On the part of the selective principal claim added at the trial.

A principal lawsuit and a counterclaim shall be deemed simultaneously.

1. The reasoning for the court’s explanation on this part of the facts of recognition is as follows, and the corresponding part of the judgment of the court of first instance is the same as that of the corresponding part. Thus, it is acceptable in accordance with the main sentence of Article 420 of the

The third court of first instance determined that “the building was installed to be the first lower court,” which read as “the building was removed on May 4, 2018 when the lawsuit in this case was pending.”

"Nos. 1, 2, 12, and 15 of the first instance judgment" shall be construed as "Evidence Nos. 1, 2, 12, 15, and 17 of the first instance judgment."

2. The parties' assertion

A. The instant sales contract was rescinded because the Plaintiff’s principal claim did not pay any balance under the instant sales contract by March 20, 2017, and the Defendant delivered the instant land and buildings to the Plaintiff, which must be around October 31, 2018.

Therefore, the Defendant is obligated to pay the Plaintiff KRW 3,090,000 as compensation for damages incurred by unjust enrichment or nonperformance of the duty of delivery from April 6, 2018 to October 31 of the same year.

B. At the time of entering into the instant sales contract, the Plaintiff did not notify the Defendant of the fact that the instant mobile facilities were installed over other land adjacent to each of the instant land, and the Defendant concluded the instant sales contract in the mind that it was installed and used as a warehouse on the inside of the instant land, and thus, the instant sales contract was revoked on the ground of fraud or mistake.

Therefore, the plaintiff is obligated to return 50,000,000 won to the defendant as the reinstatement.

3. Judgment on the main claim

A. Even if the seller fails to pay any balance within the effective real estate sales contract of this case by the due date, the seller has agreed to the effect that the contract is automatically rescinded, but the buyer is forced to delay the performance by providing performance.