What plans do you use when scratchbuilding?

Actually, I rarely use a plan when scratchbuilding a building. The main inspiration I use when scratchbuilding a building is to look at real or model buildings, and pick the features I like and combine them in a building I want to build. My perception of whether I can construct a particular feature also comes into play, and sometimes this means I don't build a wall or other feature the same as the real building I originally got the idea from.

An example of this is the South Forest Flour Mill. I was originally going to give it weatherboard walls, then I tried brick paper to cover plain walls, but I realized when I started to cover the walls these two ways that it wasn't going to have the desired effect - I basically built the features of the wall in the wrong order, so adding a weatherboard or brick finish to the walls was not working as I wanted it to. So I settled for a rendered effect instead, using painted 280 grit Wet and Dry Paper glued in place.

The Illinois Mineral Company stone bunker is an example of a compressed building, based on a photo I received from an acquaintance that is in the general region I model. This particular building is really the only one that is fairly close to the real thing - all the other buildings I have scratchbuilt tend to have a much higher 'imagination' content!