Basic Cheap Coop
Very small populations of young chickens owned by beginners are best served by a basic cheap homemade coop. Using an old discarded wooden pallet for the floor, build a sturdy wooden frame with open sides and top. Nail chicken wire all around and on top, leaving a square hole on one side large enough for your chickens, and place a wooden door over this so that it can be secured snugly. Bend down all wire ends and secure them to the wooden frame. On one end, attach the chicken wire with hooks instead of nails so you can open it up for cleaning. For a perch, nail dowel rods to the top edges of a short kitty-litter box. Place the box just inside the hooked chicken wire end.
Prefabricated Sheds
Older, larger chickens need more room than young chickens; they also start laying eggs. At about the same time, they need to perch while sleeping instead of simply huddling together. You can convert a new or used prefabricated shed into a chicken coop for free-range chickens. Each chicken will need about three square feet of space. Slots on the shed walls can mount porches and shelves to hold nest boxes. You may want to cut a small hole at the bottom of the main door for your chickens, but if they don't mind the human-sized door, you don't have to. Plastic or vinyl sheds with floors are the best, as they can be easily and quickly mucked out and hosed down. Do ensure that your prefabricated shed has plenty of ventilation at both top and bottom, or install your own. A vent grille at the bottom and an attic fan venting outside at the top should be plenty. You will also have to attach a yard to the front if your chickens aren't completely free-range.
Mobile Chicken Coop
A few backyard farmers have tried a mobile chicken coop for in-place composting and fertilizing. This is best for young chickens who cannot run around safely yet. A basic cheap coop mounted on a wagon or with wheels is best for this. The farmer positions the coop in a plowed fallow area. When the coop is hosed out, the residue is allowed to fall on the ground. The farmer moves the coop to another area, and the manure composts in place.
Chicken Tractor
Like the mobile coop, a chicken tractor is portable, but it's not used to compost in place. A chicken tractor is a coop mounted above a fenced yard, the whole thing built in one piece and light enough to move around a field or lawn. Instead of being free-range, chickens are penned inside the tractor. The owner moves the tractor from place to place, focusing on areas he wants fertilized, debugged, weeded and trimmed. With careful placement, a chicken tractor provides both a habitat for a chicken and natural lawn care.