1. Of the judgment of the first instance court, the parts concerning Plaintiffs B, C, F, and G shall be modified as follows:

The defendant is the plaintiff B, C, F, and I.

1. Under the main sentence of Article 420 of the Civil Procedure Act, the corresponding part of the reasoning of the judgment of the first instance (from No. 4 to No. 7, 5) shall be quoted in accordance with the facts and relevant statutes.

2. Whether the claim for return of unjust enrichment occurred

A. (1) The plaintiffs' assertion (1) based on the public announcement date of each of the above compensation plans as the base date for relocation measures, the defendant agreed to specially supply the apartment of this case to the plaintiffs falling under those subject to relocation measures under Article 78 (1) of the former Public Works Act as part of relocation measures, and concluded each of the sales contracts of this case with the plaintiffs, and in calculating the purchase price applicable to the plaintiffs, the sales price should be deducted from the cost of installation of basic living facilities under Article 78 (4) of the former

Therefore, the sales price equivalent to the cost of basic living facilities out of each sales contract of this case is null and void in violation of the former Public Works Act, which is a mandatory law. Thus, the defendant is obligated to return to the plaintiffs the amount equivalent to the cost of basic living facilities

(2) The defendant's assertion ① The plaintiff L (the original owner AC) is a successor to an unauthorized building excluded from the person subject to relocation measures pursuant to the former Enforcement Decree of the Public Works Act (amended by Presidential Decree No. 20722, Feb. 29, 2008; hereinafter the former Enforcement Decree of the Public Works Act); ② The plaintiff B, C (the original owner AD), D, K (the original owner AE), and M (the original owner AF) acquired real estate in the development zone of this case after the relocation measures base date, and began to reside therein, and thus, the above plaintiffs cannot exercise their right to claim a return of unjust enrichment equivalent to the cost of installing basic facilities against the defendant.

B. (1) Determination of the status of the plaintiffs (1) Determination of the base date for relocation measures under the relevant laws, such as the former Public Works Act, (2) Determination of the relevant legal principles (A) and (2)