My in laws live outside a city and they still paid a little over $100,000.much of their "savings" is eaten up in increased transportation costs and increased utilities (sewage and refuse). They have less money overall anyhow because the nearby jobs are few and pay crap. So unless you're referring to a homestead situation in which one is mostly self sufficient (which sounds awesome in theory to me, but I know I don't know how to farm, garden, or raise animals) and do without some utilities (like gas and electric), actually living in house that cheap isn't possible. In many places, you can't even do without utilities (even though mankind did so for centuries) because laws make it illegal to live in homes that don't have gas, electricity, or sewage services (which, of course, you must pay the local government for). Also you can't legally collect rain water. Our government (local and federal combined) have gone out of their way to make it impossible to be self sufficient.
...um, i forgot what my point was, I'm just ranting.