Here is my coop built out of pallets, just had to purchase deck screws & cinder blocks & roof shingles.
Got my shingles 1/2 price at Lowes, because the package was broken, used 4 mil plastic sheeting as a vapor barrier between the plywood roof & shingles. Also check Craig's List for wooden shipping crates (transport companies give the older ones away, and are made out of 3/4 plywood.) Remember chickens need ventilation, but do not like drafts.
Check to see if there is a local feed store near you & ask them if you can have the alfalfa scraps that are on the ground. I keep plastic grocery bags in my truck, so when I do get my feed, I can get free alfalfa.
If you are getting chicks, you will need a heating lamp, a large rubbermaid container, they grow fast, some type of lid, either mesh fencing of drill large holes in the container lid. The bales of pine shavings are about $5.00, and will last you past time time your chicks will be inside.
Build your coop & run first, and wait for a while before you get your chicks. That way you can see how the coop & run hold up during the winter, rain, wind, sun exposure. You are in Arizona? Make sure your chickens are a Heat Tolerant breed, that the coop is close to a water source. This summer in Texas we had temps over 110, and I was out with my chickens (they were 6 weeks when they went out), 4 times a day, misting them down, providing them with frozen water bottles, to keep their water cool. And blocked off the East side of their run with a tarp to protect them from the sun. My run is also under a large oak tree, so there was some additional shade. But they were panting for 3 months till the heat broke.
All it takes is one unsuspecting predator to find it's way in, and your chickens are gone.
My hubby calls me Mrs. Anel, because I am the Queen of lists and make sure everything is planned before I start. Am working on my spring garden plans now, making lists of all the building supplies I will need, and am calculating the cost, and seeing what I can find online for free.
You will need, if you are going to get 8 hens, 50 lb bag (when laying size) about every month, a little less in the summer if you let them free range. Get the pellets when they are older, less waste. Chick Start for the first 16 weeks, see how a 25 lb bag will do for starters.
Pine shaving, and feed, should run you no more than $20.00 a month. You can make your own Flock Block, type it in the search engine above, a lot of great recipes.
But, Plan, Plan, Plan, before you get the little fuzzy butts.