If you want to go cheap try craigslist. We built our coops from pallets for free. You can take them apart for you wood part of the roof. I have also seen shingles free or cheap even if you have to use different colors you could make it cute. If you don't see them ask! Shingles will be heavy! A metal roof would maybe lighter but harder to cut if needed. They also make a plastic roofing like metal might be easier to cut. Looks like you are doing a fine job so far....don't let the roof get the better of you
