1. The plaintiff's claim is dismissed.

2. The costs of lawsuit shall be borne by the Plaintiff.

1. Basic facts

A. The Plaintiff is a person who runs the interior design business, etc. with the trade name of “C”.

B. On January 5, 2017, the Plaintiff and the Defendant, on the part of the Plaintiff, determined that the Defendant “internal interior interior interior interior interior interior interior interior interior interior interior, furniture, interior, and external signboard construction” of the building located in Gangnam-gu Seoul Metropolitan Government is the construction period, and written out the standard contract for interior construction work (hereinafter “instant contract”) with the content that the contract is concluded at the time of the completion of the design of KRW 5,500,000 (the contract amount of KRW 5,500,000, and the advance payment of KRW 16,50,500,000 upon the completion of the construction, the intermediate payment, the intermediate payment of KRW 11,00,000,000 at the time of completion of the construction, the balance payment of KRW 5,50,000,000, and the construction work is completed at the time of completion of the construction work).

C. The general terms and conditions of the instant contract include the following:

(4) If the construction work is modified or added at the request of A during the construction work process or after the completion of the construction work, A shall pay B additional expenses incurred in relation to the modification or adjustment. The scheduled completion date of the construction work may be extended in accordance with a separate contract. (1) In the event of a change in the construction cost under paragraphs (1) and (2), B shall be liable to repair the whole or any part of the construction cost incurred within one year after the completion of the construction work. However, A and B may separately agree on the extension or reduction of the construction period.