I think that a lot of people who want to be reasonably well prepared for disaster, but aren't into it as either a sort of major hobby or as part of an overall lifestyle, question how much preparation makes sense to them, in terms of time, effort, expense and opportunity costs. Everybody will have to find their own answers.

To me, the standard 3-days food and water recommendation should be a rock bottom minimum goal for everyone. A two-week supply would be much better, especially if supplemented with useful skills and items beyond the bare basics. I would consider a well-rounded three month or more supply enough to make a typical family well-prepared. Beyond that, you might possibly be heading into survivalist hobby or lifestyle territory, where the sky's the limit.

But there's another consideration. A careful study of modern history reveals, I think, that the stories of the survivors of all sorts of calamities and disasters are, for the most part, the stories of refugees. Essentially, the best way to survive is often simply to either not be where the Really Bad Thing happens, or to GTFO as soon as possible thereafter.

That may mean leaving pretty much everything behind. So, your carefully planned and located bugout shelter or basement full of expensive long term foods and supplies may become an anchor around your neck if it causes you to stay when you should have fled. As Robert Burns told us, "the best-laid schemes o' mice an' men gang aft agley."

If that's so, it suggests to me that perhaps material survival supplies ought to be limited to whatever you may be able to take with you, at least for part of your journey, or else that you would have and use anyway in your normal everyday life.

It implies several other things, as well. The importance of having good situational awareness, for one. The value of possessing portable skills and preferably portable assets, for another.