I believe there is disbursed camping in the national forests. I have not done any; normal national forest campgrounds seem to fit our needs. Our favorite is Sherando Lake, site A29 or A30. Cost is $10 after the senior discount. You could also camp at North River for only $5 per night.
We have a 24 ft Tradewind and this works fine. For boondocking smaller is better so you might look for a Caravel
, Globetrotter or Safari (17-22ft). Take a good look at all of them and buy the best one that you can afford and just go camping.
Solar is really not needed. We can easily go 5 days on our 2 golf cart batteries.
Good luck, Dan