I've removed a few duplicates David posted.
These are my biggest in my IRA.
RGR
AGNC
LSI
UPS
IVV
Like most people I have other assets, like home equity, a couple well maintained vehicles, life insurances, etc.
I think the prepper context is worth understanding, but maybe not worth a panic.
I recently was reminded that my TDAmeritrade brokerage account can take 2 business days before the funds from a recent trade are available to withdraw.
I could immediately make trades with that money, but not a withdrawal to my bank. Further the ACH bank transfer might take 3 business days beyond that..
That's a long way of saying, if there was an acute economic crisis and I hit the "sell" button, it would likely be a week before those funds came into my savings account. And that still is not "cash in hand". I'm not advising folks keep $10K in bills under the mattress, but it is a logistical reality to be aware of.