13. Most normal people have candles and flashlights
and enough canned food to tide them over a few rough days. Some of the richer ones have generators and enough gas to get them through two or three days.
What's totally wacko is trying to prepare for a full cultural meltdown. There is really no way to prepare for something like that, no matter how many guns you have. At some point, you're going to need services from somebody else and that's going to cost you a lot if you start out by pointing a gun at him or her.