That's a good question- I guess if I had a choice, I'd get and keep an old Army Duece & a half 5 ton truck as a bugout vehicle. My brother-in-law actually has a neighbor who keeps one in his carport. The downside being license, insurance, keeping it in running condition-- they aren't something you take for a spin to the grocery, normally.
When we had the wrecker and welding services, the wrecker and service truck were handy to have, as they could carry a fair amount of cargo. Alas, the service truck got sold, and the wrecker needs a new master cylinder- to say nothing of a current license plate and insurance- to make it roadworthy & legal. I still use it as a boom truck around my MIL's old store, but stopping 8,000+ pounds of truck with the hand brake is a little hair-raising...
Aaaah, there lies the problem, if you don't have neighbors you can collaborate with. We don't even know where we're moving, but I have a list I'm calling later on tonight for rentals.
My bf has a 60's Suburban that is almost fixed, but his friend is working 12+ hrs a day and cannot complete. They were going to put in an automatic transmission so I could drive it, but lets just get it running. Keeping all vehicles in gas makes sense, and also keeping jerry cans filled is a good idea.
Such a pain to take care of yourselves and loved ones : (