I'm not sure how Dennis is going to be able to afford a house at this point. He's not working and age 65. If he sold everything he owned and put it into a house, that might not leave him enough for repairs or taxes, depending on whether he gets an age 65 exemption. He also has health issues.
If he sells everything, he might be able to buy a rural piece of land to park the RV on, but that will be subject to zoning and local laws. It's getting harder and harder to do that, although it's not impossible.
The big advantage to owning the land is that the landlord has no say about the dogs or how long the RV can stay there, or even the age of the RV, again if local codes permit. Some codes say the RV or manufactured home can't be more then ten years old. That needs to change.
There's also utilities to consider and where to shelter from bad storms (if they are a concern).
Maybe Slab City? (I'm joking)
en.wikipedia.org
Added: Found a county in MO with NO ZONING
www.lawrencecountymo.org
View attachment 415561 Lawrence Co, MO