Patty, I lived in the Sonoran Desert for a couple of years, when I worked at a national park at the US/Mexico border. The trick that they did there was to turn off the water heater in the summer. The heater was in the house so was cool, and the water coming in through the cold tap was hot from the pipes running underground in the local environment. You literally turned on the cold tap for hot and cooled it from the hot tap that came from in the house. I hope this helps.

Is there a covered parking area? Can you park the RV in the shade and sleep there? Even though it's awkward, there is something about moving into a new place and being resourceful as you adjust in the beginning without all of the furnishings. When we moved into this house in the first few weeks, while I was painting and putting down tile floors, I set up two regular beds and the cot in the corner bedroom for me and the kids. (I slept on the cot.) It was camping out in the house, and as I got more space ready, we moved furnishings and each eventually had our own rooms. Until I had the tile surrounds up in the bathtubs we used a galvanized tub in the back bathroom for baths.