Yes to impossible to prep thoroughly and yes, best to have started self-sustainable living long ago. Listen if they choose to, it doesn't matter how much you have saved or how many crops and animals you have - they can ruin you and take your stuff. Also, as someone who had a little self-sustaining farm, realize if the SHTF, your animals and crops, even if you protect them with weapons and dogs, they could end up in someone else's belly. SO barring the extreme, because Mad Max be mad, people should have a cash cushion that is larger than normal and as big as you can make it. If you have taken money out of the market, you have to gird up your loins and jump back in and you must decide when. Staying out because you are scared will keep you working forever. Pay off your house (or pay it down by getting a 15Y and double up on your payments when you can). Stock up on some non perishables in case it gets ugly. There are other things you can do, but those things are doable for everyone. Also don't sit around worrying. Just get on with doing the right thing. If you do, things are less likely to go sideways.