No matter what property you find you will still have to find what the zoning laws are for that county if they allow an RV to be parked on it. You are going to find that most do not. And almost all that allow RV 'parking' on residential property will not let you 'live' in the RV.
And regarding the property you are looking at now with the tear down manufactured home? If you are thinking of flying under the zoning wire with your RV on that one. Don't get real excited. The electric company comes out to hook up the electric and they are required to report back to the zoning. If its a tear down they will not supply you with power when you call to have it turned on in your name. They will tell you you have to bring it up to code first. AND they no longer will feed to a pole on an empty lot. I tried that and it didn't fly. They have changed a lot over the years regarding power and zoning.