This is how to get your BOL bunker set up for cheap and easy.
It's a really simple construction system using dirt and billboard tarps. You could do this even in a very remote location, as the materials required are very lightweight.
The basic design is posts, then stucco mesh, then thick...
Check out this web site and the idea of "super adobe". Looks simple, costs little and yet is rock solid.
Tests showed that it was still standing after supporting twice the load that would have crushed a traditional sloped roof house.