I know when I'm shopping for my next bunker away from home, I'll be hitting up Studio Morison for ideas. If its "Escape Vehicle #9" is anything to go by, not only will my post-disaster abode be practical, but I'll look good sitting in it during those nasty nuclear winters, too.
While more of an art piece than long-term living chamber, EV9 has a lot going for it if you do need spend a bit of time inside.
According to Dezeen's Ali Morris, the above-ground bunker can comfortably house two and sits a fair distance off the ground, so you don't have to worry about roaming animals and/or mutants.
You can get in and out via a trapdoor and ladder and the whole thing is built from two layers: a "specially commissioned aluminium expanded mesh" and a "membranous weather layer of yellow PVC". Morris also mentions the roof is insulated to keep occupants from freezing to death.
That said, there's not much else inside, other than a metal floor and bed, so be sure to bring a can opener and a few tins of soup if you do decide to spend some time inside.