With snowbird season upon us, it may be difficult to find a location to stay for an extended period of time in the greater Phoenix area.
In the Scottsdale area is Eagle View RV Resort on the Fort McDowell Indian Reservation. The RV resort is on one side of the highway with a casino on the other.
If you don't mind the lack of full hookups (water and electric only), there is McDowell Mountain Park which is part of the Maricopa County Park system. There is a two week limit which would force you to move. There are however several parks to choose from. All have a dump station.
Cal-Am resorts in the Mesa area might be another option to try.