My materials so far have been $364, so about twice what I was figuring to start with. This is just for 35 sheets of OSB, 2 10' 1x4's (for roosts), and 2 rolls of roofing paper (cause all of our tin is used). I still need to get the hardware (hinges, locks, nails/screws, etc.), and the blocks to set it on, so the dog can get underneath to keep the rats out.
I've decided to go with a 12x12, but this will have 8-3 1/2' x 4' 'pens' on one side (at least), and 6 3 1/2'x4, and 6 3 1/2'x4'x1' quail/chick pens on the other side. These are figuring each as 4' high, which is not necessary except for my lakenvelders. Most of my birds are bantams, so they don't need much height (thank goodness!).
Each pen will be covered top, bottom, and sides, with OSB board, with wire fronts and a vent in the wall in the back of the pen. I'm not sure how to make it so it can be opened/closed at will. There will be doors on each end (I'm thinking a dutch door for one end, so I can keep the feed in there as well), but it is still very much in the planning stages as far as the interior goes. Hopefully the main frame will be finished Thursday, and I can work on the interior later on. Probably trial-and-error it a lot, which is why I got 5 more OSB boards than I needed