All appeals are dismissed.

The costs of appeal are assessed against the defendant.

The grounds of appeal are examined (to the extent of supplement in case of supplemental appellate briefs not timely filed).

1. As to the grounds of appeal on State-funded local highways, a road that falls under arterial facilities prescribed in subparagraph 8 of Article 2 of the Housing Act, i.e., roads located outside the relevant housing complex, notwithstanding its length or width, includes roads that connect a road located outside the relevant housing complex to roads of the same kind located outside the relevant housing complex (see Supreme Court Decision 2012Da3303, Sept. 26, 2013), and the part of the lower court’s determination is justifiable in light of the aforementioned legal principles, which is a road installed within a public works zone by a project implementer and is in charge of the entrance of a housing complex, etc. inside the relevant housing complex, etc. and other roads that connect outside the relevant project district, and is essential facilities for the achievement of the functions of the housing complex, etc. and the passage of all residents therein (see Supreme Court Decision 2013Da29509, Jul. 23, 2015).

There is no error of misapprehending the legal principles on basic living facilities and unjust enrichment.

2. As to the ground of appeal that part equivalent to the ratio of the size of a motorway to the total size of the road within the instant project district should be excluded from the cost of installing basic living facilities, among the cost of installing underground roads, tunnels, bridges, and bridges, the lower court, based on its stated reasoning, excluded from the cost of installing basic living facilities.