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Cheap, older motorhomes are usually the cheapest route, and in my experience, usually the best route as well.
I can choose a floorplan I like, and one with a generator will never run out of power. I can buy a move in ready full featured home on wheels for under $2500, even with todays over inflated prices.
They’re easier and cheaper to fix than anything newer, and at 40+ years old have already proven themselves to be an oldie but a goodie. With a little preventative maintenance, they’ll likely outlast most of the newer ones. If not, at least you have a minimal amount of money invested in it, and it’s probably still worth what you have in it.
An ozone generator can kill any mold, bacteria, insects, rodents, and germs, no matter how deep they’re hidden. It’s what the pro’s use, and they’re not very expensive. Leaks are usually pretty easy to repair, and interior damage is usually more cosmetic than structural. The biggest expense is usually new tires if necessary.
I don’t waste money on solar, lithium batteries, or any other newer nonsense. I use them as they were meant to be used when new, with no upgrades required, needed, or desired.
Comfort, convenience, reliability, sustainability, and safety are high on my priority list, and dirt cheap older motorhomes check all those boxes.
"Tough people thrive in tough times." ~ Local Yocal