A couple of years ago I visited the Western Pennsylvania Model Railroad Museum outside of Pittsburgh. http://www.wpmrm.org/ They had some buildings on their layout that had been made by using scale drawings that they had made. They cut out and pasted the sides and fronts to cardboard and assembled them into structures. They are replacing these with a finished scratch built structures as they get to them. They were for the most part background structures and I had to be told that they were simply paper buildings – they looked good.
I bought a CAD program and started messing with structure drawings and my first effort was a trailer court for our club layout. It sits about five feet back from the edge of the layout, has trees, vehicles and people. Most visitors don’t realize they’re paper mobile homes. I printed the sides on heavy Strathmore paper and reinforced the corners and edges with 1/8” stripwood. The most recent building I made was a hotel that went on top of a mountain. It too sits about five feet from the viewers but to give it forced perspective it’s 1:120 scale (our layout is HO). Here’s a picture of Ski Mountain Lodge