Quoting DARK spawn
It is a little disapointing that there are only 2 exterior walls, but the overall all effect more than makes up for it :)
Yeah, I don't build these houses for playing, they are for display in a diorama. I realized that if you use big shop windows on the ground level, and there is no interior in there, it looks bad. So I started filling up the empty shops. The internal size of the shop is as big as the house, so I can put in a lot of stuff. It is not in proportion with the size of the building, of course. But that would be cost prohibitive, each house would have to be much bigger than these.