A) I'm with RGVAg on this one.
B) If you must plant turf, PLEASE don't use St. Augustine. Use Bermuda. St. Augustine just needs way too much water. Regardless of whether or not McAllen is enforcing water rationing, you should try to be conscious of the severe drought situation and use as little water as necessary.
Establishing a St. Augustine yard does pretty much the exact opposite of that.