This is a topic we are really interested in and seriously looking into... so here goes a hunk of introductory post:
To own land and boondock on it is almost impossible in America from what I can find - and it should be that way in highly populated areas if the people there want it that way. (Like it or not, most permanent residents don't want transient people.) My goal is to find land that I can buy either very cheaply or purchase by land contract with the owner direct without a bank - and do so in a nice area fairly close to civilization. That is entirely possible - and I know a guy who made a living flipping those. (Think "unpaid taxes" and search at the county office.)
I want to build (cheap) and I want to live in my RV while I do it - and that's possible, too, very often. (More commentary below.) Land with house = home base. Simple: I'm getting old (in my 60's) and I'd rather not die on the road.
The biggest issue, really, with building (anything) to have a "home base" piece of property is the requirement to hook up to the grid. That can cost more than a cheap house in some places...! In some cases you can escape that by finding a property that already had hookups so you don't have to pay for installation, (someplace that had a mobile home on it) and find out if you can do the hookup to service by yourself (which is often allowed). That approach brings the price WAY down (if you can find it), and if you want to put in solar and sell your power TO the grid, go for it. No one says you have to *use* what you are hooked up to.
The idea that I have to live in some stinky Texas desert to get by is just off the charts unacceptable to me. No medical care, hot as Hell in summer, frozen on winter nights, and no help, friends or shopping as far as the eye can see. That price is a bit steep to get left alone!
The idea that you can get away with something is a great way to get in real trouble in any county with a strong population - which is where most folks want to be. That's the trade-off: Live in the middle of nowhere or build.
If you will build a house on your land, many counties will allow you to live in a RV while you build, but many have time limitations and want to see you move to completion - and they will hold you to it with an inspection put on the schedule. If you say you are going to build, build something. (That doesn't mean it has to be huge. Find a county that has small square footage requirements.)
It is worth note that building does not have to be a mansion. In many counties you can build a certain square footage with no permit, so talk to the county guys. Tell them you are on a tight budget, and ask them to *help you*. Now, if you're broke and have no income you have a problem, and that means "say hello to the desert", but if you want a real life close to medical care, etc. (which is important at our age) and want to build, then find a used mobile home, strike a deal with a distressed owner, and move that onto your (cheap) property. ===> Legally done, very fast. Use that as home base...
A distressed mobile home could be put on your property for $10 - 15,000 with no bank and no down payment if you find the right distressed sellers; then the cost is to move the thing, which is not so bad, all things considered. You can make payments with the owner any way you agree.
The easiest way is not to build and not to buy raw land, nor does it have to break the bank.
There is no restriction that says you can't buy some really distressed cheap house sitting on some kind of isolated land, once more directly from the owner without a bank and on whatever terms you agree to. OK - the house is awful - but you now have all the legal BS covered. Find a distressed seller, buy their place for dirt, and park there all you want. That is something you could "get away with".
I'm not up for doing these because I simply want nice views and don't want to live in a something that looks like rotten cardboard that I could push over with a spoon. I want to design and build cheap - but new.
Travel for a year, find the property, live in the RV while I build. I have friends who did that - worked great, in a suburban area. But they had strong incomes, and we don't...