Here are some pictures of a coop that my father-in-law built from 6 old house windows, some 2 x 4's, and some 4x4's. I asked him if he could give me a "set of plans", but he said he just did a little each day, sat down and looked at it, then did a little more. It sits on a table made of 2x4's and 4x4's for the legs. Underneath it, we put the nesting boxes on a platform with the access to get the eggs from back. The first picture is the front, the second picture is the side view (with the automatic "diner" in the foreground), and the 3rd picture is the back view.
Also, he put a "trap door" inside the coop so I could easily clean it out. There are 3 roosting bars on the inside and our 12 girls are quite happy with it.