1. I fulltimed in a small Class C for a year. During that time, I attended college online, was employed as an editor, also online, and migrated between California, the Pacific Northwest, and Arizona. I stayed exactly one night in an RV park (and that was a mistake). I think people have been brainwashed into thinking that a RV is not a self-contained living unit and that you need to be plugged in and hooked up any time you are parked for longer than five minutes. Nothing could be further from the truth. (And BTW, there are plenty of ways to take showers in any setting--I took a Navy shower in the rig about one day in five, and used a separate water supply most of the time. A camp shower bag in the sun holds about a gallon and makes for a dandy shower.)
2. It's trivially easy to find a place to park for the night, even in Southern California. It's also easy to find a wifi signal almost anywhere there is cell phone reception--I have a Verizon Jetpack hotspot. The vast majority of such places are free, and forest service campgrounds are $10 a night.
3. The most valuable piece of advice I've gleaned (and if you know the literal meaning of "gleaned"...) from this thread is that it is quite possible to find a good mechanically sound chassis for $10K, and that that is what matters.
4. 21-23 feet works for me because I don't need any more interior room and maneuverability is important.
5. I may choose to tow four-down (meaning I get rid of my Mazda), but my understanding is that even vehicles that are "approved" for that can develop some serious problems, usually in the transmission. A tow dolly seems to be the most sensible solution (keeping the Mazda), but a trailer may be better. I've towed hundreds of vehicles on dollies and trailers--my late father and I owned a wrecking yard.
6. I am absolutely not constrained to a single location or area, and the sensible option would seem to be to spend winters in AZ or southern CA rather than expending a huge amount of effort and money trying to winterize the interior, which given the nonexistent insulation in most RVs, would seem to me to be only sort of effective anyway.
So I'm going to look for a mechanically sound rig within my stated budget. I like the idea of sticking with a later Ford (maybe the V-10) with electronic engine controls--there's just too much to go blooie otherwise. Obviously, at my price range, I'll be looking at something with higher mileage, but if it's been well maintained, I might be able to deal with that. The house will be a disintegrating death trap, but I'm fine with dealing with those issues as they arise. The important thing is to be able to keep rolling.
