1. The Defendant: (a) KRW 397,928,741 for the Plaintiff and KRW 5% per annum from October 25, 2017 to October 26, 2018; and (b) for the Plaintiff.

1. Basic facts

A. On June 26, 2017, the Plaintiff entered into a subcontract with the Defendant to pay part of officetels as a substitute (hereinafter referred to as the “instant subcontract”) with respect to the construction cost of KRW 350 million (excluding value-added tax; hereinafter the same shall apply) and the construction period from June 26, 2017 to August 20, 2017, among the new construction works of Matel Etel (hereinafter referred to as the “instant officetel”). The Plaintiff entered into a subcontract with the Defendant to pay part of officetels as substitute (hereinafter referred to as the “instant subcontract”).

B. The Plaintiff completed the instant construction on October 20, 2017, and the Defendant paid the Plaintiff KRW 40 million among the construction price as above, and KRW 27 million on July 13, 2017, respectively.

C. On August 17, 2017, the Defendant concluded a sales contract with the Plaintiff to sell the instant officetel F in the amount of KRW 335 million (hereinafter “instant sales contract”). D.

On June 28, 2018, including the above F, the Defendant completed registration of the preservation of ownership in the name of Nonparty G as to the remaining 13 households of the 24 households of the instant officetel, which have not yet been sold.

E. On the day of registration of ownership preservation, the Defendant concluded a real estate security trust agreement with H as to the said 13 households, and completed each registration of ownership transfer for the said 13 households based on trust in the name of H in the future.

[Reasons for Recognition] Facts without dispute, Gap evidence Nos. 1, 8, 9, 11 through 16, 24, Eul evidence Nos. 2 through 4, the purport of the whole pleadings

2. The plaintiff's claim for the remaining construction cost

A. According to the above findings of the determination as to the cause of the claim, barring any special circumstance, the Defendant calculated the remainder of the construction cost after deducting the amount of KRW 67 million paid by the Plaintiff from the Defendant, out of KRW 385 million of the agreed construction cost, including value added tax, to the Plaintiff who completed the construction work pursuant to the instant subcontract, from the amount of KRW 385 million of the agreed construction cost, = 318 billion of the construction cost, i