I think a lot of you guys are assuming costs that don't need to be there.
1) Live in a vehicle, and stay on BLM land, no rent, no property taxes. Fuel and the the vehicle on free waste vegetable oil. Buy a used school bus for $1,500.
2) Participte in the barter economy, use CL, trade stuff, trade labor. Clothing can essentially be had for free at garage sales and household supplies.
If you live on BLM land outside a city, you have the resources if living rural, like hunting/fishing/wood, and you could easily live on the scrap/margin/waste of a city.