Here are some models used for an underground scene.
Model of a real train station in Nieborowice, Poland. Created in Blender, textured in Substance Painter with my custom materials.
Original location: https://goo.gl/maps/ZKS99MWLuSy5taGp9
House
Doors and windows.
A Large SciFi wall with central-vents. The wall can be used standalone or of course together with other models to create a sci-fi scene.
Simple kit to create vents for buildings. Its also possible to enter this vents with your player model.