Land can be bought everywhere in all price ranges. The real hurdle is whether you can legally live there or what requirements there are, due to zoning and building codes.

I think the easiest way to get a self sustaining home with as little legal issues as possible is to buy an already legal home with the grid connection, but then just don’t use it.

If I were young and single again, I would look into auctions of derelict farms. Tear down the old building and instead build a small totally legal connected up to code cabin with water, waste and electricity connection. Then use the rest of land to do whatever actually interest me, while complying to the bare minimum of legal requirements for that land.