I would say to begin with build a sturdy fence that predators cannot get over or under. This is going to save you a ton of heart ache in the future. Here in So Cal we also need a fence to keep our birds out of site. Especially with the new code enforcement rules and regs getting more intense all the time. Out of site out of mind. Build plenty of pens, Good pens, use small wire to keep the small birds out. I built about 50 6′ Diameter Round pens a couple yrs ago, They are also 6′ high with a solid roof and frame. I absolutely love these pens. They cost me some where in the 100.00 range to build each but they are awesome. They are big enough that the birds can get great exercise and the soil seems to stay loose longer and doesn’t get packed down so quickly. Just a few tips, also build your pens with a jump board to keep water off the ground, and where you can easily access from outside to change out. Also keep roosts away from roof and side walls to keep your birds feathers in excellent condition yr around. Thanks