A. The Plaintiffs are prospective occupants or occupants of the F apartment located in Seongbuk-gu, Sungnam-si (hereinafter “instant apartment”), and Defendant A Co., Ltd. (hereinafter “A”) entered into an agreement on the joint purchase of home appliances, which are co-purchase and lending, with the system, on May 4, 2016, with the committee of prospective occupants of the instant apartment complex (hereinafter “the council of prospective occupants”); and Defendant B Co., Ltd (hereinafter “B”) entered into a contract on the joint purchase of home appliances with the Plaintiffs for the installation and construction of home appliances, and Defendant B is the actual business owner of Defendant B, and Defendant D is the representative director of Defendant B.

B. The prospective occupants of the instant apartment complex constituted the council of prospective occupants, which is a group representing prospective occupants in the Internet carpet group.

On May 4, 2016, G president of the prospective occupant council concluded a joint purchase agreement (hereinafter “instant joint purchase agreement”) including the contents that Defendant A and prospective occupants of the instant apartment complex hold an exhibition to jointly purchase electronic equipment necessary for each household (hereinafter “instant joint purchase agreement”).

The main contents of the above Convention are as follows:

The council of prospective occupants (hereinafter referred to as the "council") and the defendant A (hereinafter referred to as the "manager") shall enter into an agreement on joint purchase as follows:

The purpose of this Convention is to prevent disputes that may arise between the council or the enterprise participating in the joint purchase (hereinafter referred to as the "participating enterprise") and the prospective occupants, and to ensure that the council provides the prospective occupants with goods equivalent to the items of the joint purchase at reasonable prices for the convenience of the occupants of the apartment of this case or the prospective occupants of the apartment of this case.

Article 2 (Definition of Terms) (1) The term "joint purchase" means a joint qualification of eligible occupants.