1. The plaintiff's appeal and the defendant's incidental appeal are all dismissed.

2. Costs arising from an appeal and an incidental appeal shall be respectively.

1. Basic facts

A. The Plaintiff is a corporation whose purpose is to install machinery and equipment works, and the Defendant is a corporation with the purpose of heating and cooling equipment and wholesale and retail business prior to living prices.

B. Around May 2015, the Defendant contracted the Asan City Urban Residential Housing Facilities and Machinery Fire Fighting Corporation (hereinafter “Asan Corporation”) to the Plaintiff around that time after receiving a supply of the Asan City Residential Housing Facilities and Equipment Construction Corporation (hereinafter “Asan Corporation”), and then subcontracted the Asan Corporation to the Plaintiff at KRW 51,219,768 (including value-added tax). The Plaintiff performed the Asan Corporation since that time.

C. Around June 2015, the Defendant subcontracted to the Plaintiff the Masan E (hereinafter referred to as the “Masan”) and the Southern F (hereinafter referred to as the “Seoul F (hereinafter referred to as the “Seoul F). Around that time, the Plaintiff performed the Masan Construction and the Southern F (hereinafter referred to as the “Masan”).

On September 14, 2015, the Defendant subcontracted the Plaintiff with construction cost of KRW 1150 million (excluding value-added tax) from September 14, 2015 to December 30, 2016 during the period from September 14, 2015, the Defendant agreed to pay advance payment KRW 500 million (excluding value-added tax) to the Plaintiff. The Defendant agreed to claim and pay the remainder of the construction cost as the progress payment each month, and the Plaintiff started the Pyeongtaek Construction from around that time.

E. On September 24, 2015, the Plaintiff received transfer of KRW 550 million from the Defendant, and transferred the money to D/O Construction Co., Ltd. (hereinafter “D/O”) on the same day, and issued sales tax invoices by designating the Plaintiff as the supplier or the Defendant.

F. On November 12, 2015, the Plaintiff and the Defendant agreed to suspend the construction work and settle the construction cost. The Plaintiff received from the Defendant the construction cost of KRW 22 million as the construction cost of the Eunpyeong Construction on September 25, 2015, KRW 33 million on November 12, 2015, and KRW 10 million on March 17, 2016, respectively.

G. Around March 2016, the Plaintiff completed the Asan Corporation.

[Ground of recognition] Facts without dispute, A2, 3, 4, 5, 6