I have galvanized corrugated roofing for a really good deal. The sheets are 2'4" wide, and I have some 8' and 10' sheets. There might be some 12' sheets too. I don't have a lot left at this discounted price, but it is $1.35 a foot. That makes an 8' piece $10.80 and a 10' piece $13.50. It's a really good price for the material. I have some heavier galvanized metal too, also priced really well. If you decide you want to use metal, message me. I like the galvanized metal, and plan to use it on my new coop because I have it and it will match my barn. But the other poster's ideas here are good too. Good luck with your build!