I already owned my minivan. I spent $2,000 for all the solar and wiring. $300 for my fridge. Maybe $250 for my cabinetry. Maybe, maybe another $400 for other things that I didn't already own. I've lived in it for about 3.5 years. So that's (2,000 + 300 + 250 + 400) ÷ (3.5 x 12) = $72.23 per month for rent and electricity. I'll probably upgrade to a bigger van in a couple of years. So that's really more like $45 per month, when I spread it over 5.5 years.
Most of the year I barely travel at all, other than to go into town to get supplies every three weeks, so my fuel bill is way less than when I had a job in a city. When I do travel, I'll go a few hundred miles then stay for a few weeks. So, let's estimate 300 miles ÷ 21 days = 14 miles per day. That's far less than my regular commute and weekend activities used to be. Plus, I get to go hiking every single day.
I pay about $4 per month for water, and $25 for a shower and porta-potty dump, so that's far less than most apartment dwellers pay for water and sewage.
My food, phone, and internet bills are the same, except I'm not tempted to eat fast food all the time. I treat myself to a nice pizza when I go into town and I appreciate it more. Because I drive my car less, I have fewer repair bills. My mechanic says I probably got another 100k miles in this thing.
So, yeah, I think I'm saving a little bit of money.