I believe you were alluding to the 17yo being out of the house next year and just the 2 of you doing this adventure. That will help with spacial concerns, but you won't have the help of the big kid around.
And unless you are doing minimalist, boondock living with very little, RVing is expensive.
Just to start, you'd need something very reliable and liveable. Hard to get there for under say $60k initial investment. Not counting the challenges of winter time, you'd have to go south in be winter to make that work and don't want to be in 100deg weather living in a can in be summer. Homeschool is the only real option and can u do that working full time?
Campsites with hookups which you'll need to full time in comfort another $1000? a month.
I'd estimate close to $2k a month in fixed costs plus everything else it costs to live day to day.
You can do the RV/camping dream cheaper in little spurts and trips IMO because it's not full time and you can cut costs vs a comfortable full time setup.
Little pop up or camper behind, not he Yaris, but a reasonable daily driver vehicle.
Ability to go boondock for free or cheaper than long term camping solutions.
The $ you spend on a little camper is sunk cost but the tow vehicle does double duty.
Just more to consider.........
