Here's a downtown retail/office building I put together from a kit.
I opened the access hatch and added an access ladder.
Merchants Row IV is another standard kit. As there are 3 different retail stores, in effect, 3 different buildings all together, Dwight wanted each painted a different colour.
A shot of the rear of the building. The rear of the right building was cut back to fit the available space on the layout (a curved siding). I added a few roof-top details that I fabricated.
Here are the two buildings on the layout.