Detail this asset from Unity Store: Original Link
This is a paid asset, but now you can download Top-Down Interiors Free.
This pack is the fourth in a “Top – Down” series. Prefabs are also prepared to another camera view (first or third person) and they are completely modular: it allows you to create the interiors in any configuration.
Package contains over 380 prefabs:
– walls, floors, stairs
– carpets, courtains
– crates, barrels, pottery etc.
– sample demos and rooms
– mobile friendly textures and meshes