Radius’ shelters start at $200,000; the multifamily pod shown below goes for $2 million, plus about 25 percent for shipping and installation. They all have fiberglass shells, which are less prone to cracking than concrete and, lacking steel, won’t show up on target-acquisition systems. The bunkers can run for years entirely off the grid, which means that when a high-altitude electromagnetic pulse takes out power on the surface, you’ll still be able to operate your hair dryer. And they’re buried far enough underground to be impervious to radiation. In the event of a chemical or biological attack, you’ll feel secure knowing that the sealed and pressurized units come with specially designed air filtration that uses three different physical purifiers and an ultraviolet-radiation sterilization system.