@Meier no it's all normal modeling, just made 36 buildings and the rest are just rotated and moved around versions of the same ones. I guess with nodes it would have been faster, but i cannot use geometry nodes at this time.
Basically is a more simplified version of this technique:
https://yewtu.be/watch?v=JjnyapZ_P-g
@Meier taking the example of the video, i didn't used only one photo, i used seven different ones precisely so it could look diverse enough.
Maybe I could just auto unwrap the sides and leave some fancy material in Unreal or something to do the heavy lifting on the windows.
prob would need to group unwrap them slightly differently to get more variation.