
  Welcome to the forum, glad you joined.  
 
1. 
The location is SW desert, there is little point, I think, in letting them range, the ground is mostly bare, gravelly sand, not much to eat. But I can give them a run of 10sq ft per bird and a coop of 4 sq ft each. The run should stay dry with daily sunshine. We have lots of coyotes around, and hawks above, all in constant search for food. The coop is secure and the run will be screened with 1 inch chicken wire top and sides but I am wondering what I can do to keep coyotes from burrowing under the sides and into the run? Is there anything else about raising birds in this environment that I should know?
Some larger animals like a large raccoon, big, dogs, and maybe coyotes can tear most chicken wire and some hardware cloth.  It depend on the gauge of the wire and how big the holes are.  Bigger holes can give them a better grip.  Pay attention to the connections and gates too, those can be your weakness.  To stop coyotes I'd suggest you look at 2x4 welded wire or other similar types of wire fencing.  Chicken wire will stop hawks from going in but a big climbing predator could rip it if they can get up there.  I'd want the run tall enough so I could walk in there without bumping my head.
To stop digging predators I suggest you look into aprons.  Take an 18"  or so wide piece of wire and lay it horizontally around the outside of your coop/run.  Attach that to the bottom so nothing can squeeze through.  In sand I suggest you bury it an inch or two.  The idea is that a predator will go up to the fence, start digging, hit the wire, and not know to back up.  It's pretty effective. 
When building the run don't get too married to the idea of only 10 sq ft per bird.  Look at the length of a roll of fencing and use it all.  People don't complain of building too big once they get past the cost, but building too small can lead to all kinds of problems.  You can follow the link in my signature to get some of my thoughts on room for chickens.  If you notice, most of those are for your comfort and convenience.  I find the tighter I squeeze them the more behavioral problems I have to deal with, the harder I have to work, and the less flexibility I have to deal with issues which raises my stress levels.  The same general comments apply to the coop and that 4 sq ft rule.  Just a little extra room can give you a lot of flexibility in there.
When building a ruin, you can get more square footage with the same length of wire if you build close to a square as opposed to a long narrow rectangle.  But if you are covering it the longer span will cause more sag.  There might be some trade-offs there.  When building a coop, a standard material size is 4' or 8'.  If you incorporate that into your design you can maximize space and reduce cutting, fitting, and waste for little extra cost. 
What are your future plans?  Do you expect to get more chicks next year and integrate them?  Extra room in coop and run makes integration a lot easier. 
I don't know your elevation or how cold it gets in the winter but your enemy is not going to be cold, it is heat.  Heat kills chickens.  Sunlight does not just come in from the top, it comes in from the sides.  You need to maximize your ventilation in the coop and provide as much cool shade as you can.  I don't know which state you are in but your state extension service might have some recommendations for you.  I think it is worth a call.
2.
 I am mostly interested in meat but I think I’ll go with buff Orpingtons as they seem less demanding/easier for me to start with than the Cornish cross and other meat birds. I would butcher the majority at about 6 months and keep a few for eggs. It’s a bit cheaper to get straight run but I don’t want roosters crowing and fighting, etc. ( I have 1+ acre and neighbors with about the same) would I be better to get all hens?
Is it legal for you to have chickens or what restrictions do you face?  Some cities, towns, or HMO's have rules about that.  1 acre lots sounds like it could be some type of subdivision. 
There are so many different ways you could go with which birds to get.  If the crowing and fighting bothers you, go with all pullets.  The carcasses will not be as big but at six months the pullets will be easier to butcher, there is not as much connective tissue. 
I don't know how many you want to start with.  We all have our favorite breeds and suggestions.  You can certainly try all of one breed if you wish.  You can order a few of several different breeds and try them to see which you prefer.  Many hatcheries offer packages of mixed breeds or their choosing at a reduced cost.  These are essentially leftover pullets after they have filled their other orders.  These packages for hens may possibly include leghorns or other smaller hens that lay well but will not have much of a carcass for meat. 
Enough typing this morning.  Hopefully I've given you a few things to think about.  Once again, 
