We built a chicken coop out of a truck cap. I used as much self made and recycled stuff as I could.
Bought stuff (about $150) includes some 2x4's, 4 sheets of marine plywood for the walls, a couple PT 4x4's.
Stuff I had: 2x4's, hinges, rough cut lumber for the nest boxes (not shown in photos, 3 levels of 7 boxes per side), nails and screws, a couple 4x4's for the base (neded 4), some really heavy tarp material for the vapor barrier for the base.
Recycled stuff: Truck Cap (Craigs List), Paint and Primer (Craigs List), Plywood topped palletts (Craigs List - inside is framed with these, walls are covered inside and out. Warm in the winter).
Construction took place over two weekends. One we got the base and the basic frame up, and the next we got the nest boxes built. I had a friend come and help me both weekends, and it went quite well.
You can see the rails that the nest boxes attach to in the first photo.