This is the Chicken coop that I built recently and cost me about $275 total. If you have materials laying around this can be done for much cheaper, I purchased everything new to see how much it would cost.
I wrote an article on Survivalist Prepper that goes through all the details about building this chicken coop, you can read that here...
http://survivalistprepper.net/how-to-build-a-super-simple-chicken-coop/