Was a the local box store & the fork lift dropped a 10x10x10 portable building that was not constructed and they put it in discount area, I got it for $35 bucks and some change, I modified it to be 8x8x10 A frame with shingles, and built it on skids to be moved later by my loader. I cut my windows and framed out the inside with osb for a smooth surface. The weathering area simply landscape timbers 8x8x8 on 3 sides and the open side joins the mews. Use the google machine and look at images. my biggest cost was screws and a roll of wire. I made my windows sized for a Kestrel, and made my bow perch by welding some steel bar stock and wrapped it. Everything is pretty simple. While I strive for perfection, the bird won't care if its not exactly plumb.