In this thread I am just going to post things I am making with an eye to making some cyberpunk trash in Unity. I'm not taking it seriously at all, my main aim at the moment is just to learn how to make decent assets in Blender and pop them into Unity.

Two identical planes (not instanced) in blender.

Model one using edit mode and subdivision with extrusion.

UV map the simple model, it essentially becomes a cube against the BG image.

Place one on top of the other, move the simple one slightly above, bake normals with selected to active checkbox ticked.

Open normal map in another program and increase contrast a little, this makes it more bumpy.

Create a plane, apply as bumped diffuse with a concrete texture as the diffuse and your normal map as normal.
And there you have a complex-looking floor tile using only two polygons per tile (in my system). I had a little problem with rotation when I exported to FBX but that was solved by rotating by -90 degrees in object mode in blender, Ctrl+A, Apply rotation. Export selected object.
The car is something else I have been working on in my creation of cyberpunk assets. Being able to paint decay onto things with texture painting pleases me.