Many commercial RV parks in the Yuma area have annual leases around $3K a year plus electricity for a full hookup space. Most of the cost is concentrated during the peak winter season, it's incredibly cheap if you want to continue staying there during the rest of the year.
One example is
Rocking K RV Park in Yuma. $50 a night, $250 a week, $400 a month. $2700 semi-annually or $3375 for a year. Monthly and longer rates are plus electricity.
There are other deals to be had. I retired 7 years ago and made my home base the Escapees co-op park in Pahrump NV, one of 11 such parks around the country. The park is owned by members who paid $10k to join the co-op and is refunded if/when I decide to leave. For this I got a lifetime lease on a lot in the park including a covered patio and a nice outbuilding that I've made into an air conditioned man-cave. There's an ongoing $1400 annual maintenance fee payable at $350 a quarter which covers the cost of water, sewer, trash, taxes and upkeep of the park's common areas including a large clubhouse. The only other cost is the electricity I use when I'm there.
Pahrump is a self-contained town of 40,000 people with everything you need for daily life. Walmart, Home Depot, a couple of supermarkets, restaurants, medical care, etc. Las Vegas including the Strip and it's large international airport is an hour away via a 4 lane divided highway "over the hump." Pahrump does get hot during the summer but it's usually several degrees cooler than Las Vegas and only exceeds 100 degrees for a few weeks a year. In the winter overnight lows rarely dip below freezing. Temperatures during the spring and fall shoulder seasons are very pleasant.
