A. On March 2016, the Plaintiff entered into a contract (hereinafter “instant contract”) with the Defendant with the content that the Plaintiff implements with respect to the construction design service business, including the preparation of design drawings and specifications regarding the construction of 44,960,000 square meters on the building area, 720.34 square meters and the total floor area of 1,857.20 square meters on each of the instant lands (hereinafter “each of the instant lands”) on the land owned by the Defendant (hereinafter “instant contract”).

At the time of the instant contract, the Plaintiff and the Defendant, in principle, determined the timing and amount of payment in installments as follows, but agreed that the Plaintiff and the Defendant may consult with each other (hereinafter “instant agreement”).

B. Until June 30, 2016, the Plaintiff prepared and provided necessary design documents, etc. to the Defendant pursuant to the instant contract. Building permission was granted to the Defendant on August 25, 2016 according to such design documents.

C. However, the Defendant did not start the construction of a new building on each of the instant land, and accordingly, the Plaintiff received, at the Defendant’s request, the extension of the commencement period for one year from the Leecheon-si, taking into account the cost of KRW 3 million on August 25, 2017.

Nevertheless, upon the Defendant’s application on April 11, 2019, the building permit on the instant land was revoked. D.

The Defendant paid only 16,490,000 won out of the contract price under the instant contract to the Plaintiff.

[Evidence Evidence: Written Evidence Nos. 1 through 7 and the purport of the whole pleadings]

2. Judgment on the parties' arguments

A. According to the above facts as to the cause of the claim, the defendant shall pay to the plaintiff the remaining amount of KRW 52,756,00 (including KRW 47,960,000 (=44,960,000 and KRW 3,000 for the extension of construction period and KRW 3,00,000 for the extension of construction period) under the contract of this case x 16,490,000) which the defendant has already paid to the plaintiff.