I was going to post this under the coop tab, but I appear to have "insufficient permissions", so this will do.
I didn't have plans or anything, but an overhang next to my garage that I wanted to use. Half of it is my wood locker, the other half is now the chicken coop!
Started by pouring a concrete pad with 4x4s.
used scrap 2x4s to build what I thought was going to be a big enough space.
used scrap barn tin for a second roof (the original leaks) and insulated the walls/floor. Scrap plywood/siding to hold in the insulation.
2x4s for roosts.
Granted, I had a lot of scrap laying around, but cost so far: plywood to finish floor = $25. 2x4s to finish walls = $10. Concrete = $20. Hardware = $10. Total = $65!
There was an old hideous mailbox attached to our barn that I've been dying to tear off, so we cut holes in it and used it as a nesting box. The picture makes it look more crooked than it is. We had the white paint left over from painting the garage.
1 quart yellow pain = $10. (2) rolls of 1/4" hardware fabric = $60. total cost so far = $135.
They love the compost bin... I made the windows with scrap 2x4s and mesh so they lock and can pop out for easy cleaning. I also made wood "plugs" for them to help shelter during rain/winter.
a dozen more 2x4s for the run = $36. Hardware (hinges, locks, etc.) = $20. ten more bags of concrete to expand pad = $20. Total cost so far = $211.
My neighbor has an old barn filled with straw that I can help myself to for free, so I covered the concrete with that. I bought a bag of pine chips for inside the coop, bringing the final cost (so far) to $215! Right now they free range the garden area, which is entirely fenced in, but eventually I'll build them an outdoor run with poultry netting that'll give them everything seen in the pictures to include the compost bin. Lots of fun! Lots to learn! I'll probably end up switching to sand for the inside.