Most HOAs will not allow RV parking. Unfortunately, in late 2004 the City made it harder for builders to develop subdivisions without HOAs. So, most anything built in late 2004 or newer will have an HOA but that doesn't mean that it doesn't allow RV parking. I'm not sure why most builders included No RV parking in their HOAs but that seems to be the case here.
I've put together a list of subdivisions on the site referenced below to help people find such properties. I always recommend contacting an HOA directly since their regulations seem to change without much notice. I live an work in Casa Grande. I've seen RVs parked in NO RV parking subdivisions. I include HOA contact information for many of the most popular subdivisions in Casa Grande.
You will want to speak with the HOA and be sure to go through their written Covenants, Conditions and Restrictions as well as their bylaws if you decide to buy in an HOA.