Check out the coops pages here for ideas. I recently completed a 6x8 coop made from recycled plywood from a ball park fence (used for the walls and roof) and 2 8' foot long tables given to me by a guy that has an auction place (used them for the floor). The guy who had the plywood also had hinges, plexiglass for windows, and heavy gauge vinyl from billboard signs. Only cost me $70.00. He even cut the wood for me to fit my plans! My brother and I put it together. It isn't level or square but it shelters my babies quite nicely. We used the vinyl on the roof so I wouldn't have to buy shingles or tin.