I'll give you another perspective you won't like, but it's one you should probably hear. I think you're making a huge mistake. You're trying to solve your financial issues by selling the only thing you have of value and buying something that is going to go down in value or maybe worth nothing at all. You don't say if you're buying new or used. A used Class C doesn't command or hold much value.
Chances are, your daughter could move again and you'll be chasing your daughter around the country, versus just saving for visits wherever she might be living, probably not a good plan.
Most importantly you talk about your health and in an emergency you'll park the RV next to a military facility. So your back up plan is to live in a trailer park in a rotting RV for the rest of your life.
Personally, I think you're looking for folks on here to give credence to your plan, which I think you know is a bad idea.
Again, not to hurt your feelings, but you should REALLY think this through. Maybe stay in your home and do odd jobs to make money for trips to visit your daughter or the outdoors. You could even meet up with your friends while they camp by staying at an inexpensive nearby hotel.
If you do find this is your only alternative, your best bang for the buck will be a truck and a fifth wheel as others have mentioned. Break downs or repairs don't involve your house and you can switch out one or the other if necessary.