Located in southwest Florida
I took a long time in deciding what I wanted to do for a coop. I wanted to be able to move it (like a tractor) and I wanted it to last forever (not the cheap wood ones you find online).
(current photo of the coop)
I decided to go with a 10'x10' chain link dog kennel from Lowe's (about $299). We bought the tarp roof that was built for it (found here). But we needed the top totally hawk and owl-proof since those are the two main predators around here in southwest Florida (at least in our area). Tractor Supply sold a 'shade top' that fit the 10'x10' dog kennels ($50) which ended up being cheaper than chicken-wire across the top so we bought that, attached it to the top and then put the pitched tarp roof over it. I wanted some wind and rain breaks so we got three tarps ($8 each) from Lowes and ran one down one whole side (the back) and half way down the other two sides (attached with zip ties). This way they still have an area of the coop that is always sunny, an area that is always shady and if it's cold and windy it gives them an area that blocks the wind, and if it's rainy the tarps give them an area where the rain blowing in from the side (most of our summer storms are pretty windy with sideways blowing rain).
(the picture above is right after we built it, no chickens in it, no hardware mesh, but this is a side pic so you can see the tarps.)
Obviously the 'holes' in the chain link do provide enough space for a cat, possum or raccoon to reach in so about two feet up, all around the coop is hardware mesh (hardware cloth/wire is another name for it)..I can't remember what we paid for that but it was purchased at Lowes and we attached it all around with zip ties (LOVE zip ties). It is on the coop in the FIRST picture, it's just hard to see (the hardware mesh is also over the door as well).
For nesting boxes I bought a couple of plastic storage tubs (about $8 each at walmart), left the lids on and cut holes in the fronts of them, filled them with hay (but now we use shavings) and they use those to go into at night or to lay eggs. One BIG problem with those is they like to roost and walk along the tops of them and do a lot of pooping up there. We're working on a way to create (or buy) different nesting boxes with a slanted roof so they can't get on top of them. As much as they love their roosts they love the tops of the nesting boxes too.
~*~ UPDATE ~*~
So we had a raccoon rampage and lost all but two of my hens. Lived here 7+ years and didn't see a single mammal on our property and then after a year of having chickens we got raccoons. We've since added an anti-digging skirt all around the outside of the coop with wire and covered the whole entire top with wire as well. Since then, NOTHING has gotten into that coop. I have two solar powered motion lights outside the coop as well, they have these little panels you flip up to catch the sunlight. I occasionally see those panels flipped down which means raccoons are still climbing over the coop at night but can't get in!
In the photo below you can see the wire that runs across the top and the wire along the bottom, it also comes out and goes another foot or so for the anti-digging skirt. The hutch you see in the back left is what we had to buy to keep the girls safe in at night till we could complete all the predator proofing, we left it in there because they love it so much for nesting/laying.
We're re-doing the tarp roof this coming weekend and before summer hits, trying to decide on some sort of shade cloth for two sides as well.
I've got 12 babies in a brooder so our flock will get replenished in no time.
I currently have plans to buy six more chain link panels and expand the whole thing to 20' x 20' and add wire across the whole top and anti-digging skirt all around. I'll need that space with all the babies I'm raising. When we complete it I'll add photos :)
I also did a video because one of my friends wanted to see how we predator proofed the coop... the logs and rocks were there just to get the wire to lay flat after we first installed it.
BTW... just saw Tractor Supply has the four panel dog kennels (10x10x6) for $250 and extra panels for $80 each. These are the kennels that actually come in panels with the chain link already attached to them, NOT the cheaper ones where you get a roll of chain link and have to roll it out and attach it yourself. We will be doing the panel method again. I've been searching craigslist but haven't found any panels yet, these kennels are super popular right now I guess. So I might just have to buy them at TSC. I still have time before the babies in the brooder go outside so I'm still looking for used ones.
Some of the 12 babies in the brooder in the house right now...
Silver Laced Wyandottes
Rhode Island Red