I just finished some new holding pens for the birds. I wanted to use all new materials but at the cheapest cost I could find. Treated 2X4's ripped into 2X2's. much cheaper than buying them already to size. Coated deck screws hold the frames together. I found some 100' rolls of Bekaert cage mesh on craigslist for $80 each. They are about $150 per roll from the manufacturer. The dividers are held in place with staples so they can be removed easily if I need to make a bigger cage. The door latches were made from scraps of cage wire. The unit breaks down into four pieces (base, lower section, upper section, roof) and can be disassembled in about 10 minutes. The total cost of materials divided by the number of individual cages equals about $14 per cage.
The wife calls our yard "Chickenville" because we have a mansion, condos, and now an apartment complex
... When I turn all the lights on in the pens for extra hours of light it looks like a small town in our yard.