Maybe I can help with a few of your questions -
1. Many campgrounds/resorts will have daily, weekly, and monthly rates. Normally the weekly rate means you get the 7th day free. The monthly rate will be excellent but you will most likely pay for your electricity usage.
2. The best way to save money is to not travel so much. Stay at least a week so as to get the discount. This also saves on fuel cost. Do the math. You can drive 200 miles every day and pay the daily rate for 30 days. OR travel just 4 times a month and pay the weekly rate. OR travel one day a month a pay the monthly rate. This why the cost of a month can vary so much.
3. RVs/campers/5ers are worse to heat and cool then your house. My electrical bill for month in the winter last year in the Phoenix area was about $100 - $120. I heated electrically most of the winter. I can only imagine what the bill would be for cooling one in a hot climate. It sounds like you may be a heavy electrical use customer. If comparing monthly rates ask what the KWH rate is. A few pennies makes a big difference.
I use RVparkreviews.com to find good places to stay. Suggest that you pick a city and check out all the different CG rental costs to get an idea of what you're looking at.
As stated before, check out Williston Crossings. I stayed there for a winter. But they may be a 55+ park. Also Cochise Terrace in Benson, AZ. Really nice place.