1. The plaintiffs' primary claims are dismissed.

2. The plaintiffs, Defendant C, and Defendant D, respectively, KRW 30,339,914, and Defendant D, respectively.

1. Basic facts

A. The Defendants’ status and the extension of the building of this case without permission) Defendant D’s status on December 20, 2010, the first floor underground of reinforced concrete structure and the second-class neighborhood living facilities building of 9 floors above ground, located on the land and its ground in Gwanak-gu, Seoul Special Metropolitan City E and its ground (hereinafter the above land and buildings are collectively referred to as “the instant land”; and “the instant building”.

(2) On June 5, 2012, Defendant C received registration of ownership transfer from other co-owners with respect to the share of 1/2 shares in the instant land and building on June 5, 2012, and owned the instant land and building jointly with Defendant D, and the Defendants were conducting the public announcement source business in the instant building. (2) On the other hand, from around 2013, on the nine-story rooftop of the instant building, the total area of 90 square meters on the rooftop of the instant building was extended without the permission of the competent authorities.

(A) The part without permission extended as above is indicated in the building management ledger as 45.81 square meters per floor, 11.28 square meters per floor, and 11.28 square meters in the real estate brokerage office of the 1st floor as to the 1st floor among the buildings in this case. Since around 2013, the part of the 1st floor real estate brokerage office was extended to the 1st floor parking lot exceeding the area in the above building management ledger (hereinafter the above unauthorized part is referred to as “the part of the 1st floor parking lot”).

B. B. (B) The Plaintiffs entered into and implement a sales contract on February 27, 2013, through the brokerage of Licensed Real Estate Agent F, for the purpose of operating the notified source, purchase of the instant land and the instant building owned by the Defendants and the facilities included therein in order to comprehensively acquire the Defendants’ notified source facilities from the Defendants, with a total of KRW 2.2 billion, but the down payment of KRW 220 million is paid on the date of the contract, and the intermediate payment of KRW 300 million is paid on the date of the contract, in lieu of succeeding to the obligation to return the lease deposit with respect to the instant building, and the remainder of KRW 1.68 million is paid by April 1, 2013, respectively.