If you have any skills and can invest the time check craigslist for free pallets and lumber I built my 4x9 with extended nesting area I've as many as 6 hens and a rooster the size of a turkey in there
If you don't use hardware screen on the floor or concrete you will get rats inside. the chicken usually treat them like family except they do eat a lot of food
Possums raccoons will steal bodies leave only feathers. And climb fences
Get the largest rooster you can. He should try to protect his flock once he learns what it is to him