Here's what you do...prioritize the doom. You can really only prepare for pipsqueak sized doom and there's not much to fear there...like all the banks failing at the same time, tornadoes made of fire, that sort of thing....so you can have some food and water, cause that's good for even non doom level screw ups in the supply chain, but once you graduate to doom 102?...there's no escaping it with a mere cache of food and water. Giant solar flares that bake off most of the globe, cat-7 hypercanes made out of toxic blood platelets, mag 12 earthquakes and 1,000 meter tidal waves...that food and water is only going to good for about 10 minutes. Get to more advanced doom?...Massively dense invisible stars smashing the entire solar system to bits, the giant natural gas reserve under our very feet right now exploding and launching an entire hemisphere into space, annoying big eye aliens coming to eat us, junk like that?...we're never gonna escape it, so why fear it?...besides...if you're older than 20 years old?...you've already lived past some of the most horrific dooms that never happened...so just embrace the horror and ride it like ya stole it!...