Well.. the structures took me maybe an hour to pack together. in another 30 minutes I could prolly divide them. It wouldn't make much sense tho since they are only placeholders for more detailed meshes. It's easy to make a city/iterate like that. It's something I learned while I was making my game. You begin with really basic structures and then replace as you go. It gives you a really nice way to see how things work and overall look before you pour hours into details.
Haha no no, I didn't meant "to separate" any mesh. Unless those 3 houses are a single mesh for example..