Greg,
I've moved way to many times and started over just as many. This move will be your last, so make it the right one. In your late 50's and willing to lowers your expectations so that if it isn't spectacular, I'm okay with it because the next one might be better, who are you trying to convince. By the time you get there, clean it up to your liking, and build a shop, you're more than a few years into this short term.
From reading your contributions to this forum, I know that you're not one to intentionally hurt or antagonize others but...
I am in better shape than most guys my age. I don't take any medications, I don't have any chronic ailments and I am still quite capable of doing what I have done all my life. I'm not as strong as I was when I was in my 20s and 30s but I still have a lot of life left in me.
The wife's parents are in their 80s and don't have a lot of time left. Mary would like to live closer to be able to see them more than once a year. Each trip is 12 hours by car. We don't fly because we prefer to have our car there and because holiday travel sucks.
This isn't a matter of us moving in with them as caretakers. The possible relocation would allow some contact with both families.
There are some issues that would put a kink in the works though.
I plan to use some sort of storage container for the car parts. Some of the properties we looked at have HOAs.....many times, these organizations prohibit storage containers on properties unless there is an open building permit.
Some HOAs require neighborhood approval before any additional buildings can be erected and they often must match the appearance of the nearby structures.
The shop I have here went from bare dirt to a framed and covered building in 3 months. I'm still capable of doing it again. I didn't retire due to any injuries or limitations, I stopped because I wanted a break from it.
This latest consideration is something that the wife wants. I am not against it but to be fair, she has been 100% supportive of everything that I have wanted to do since day one.
Tennessee is still a goal. I do prefer the green. I want the freedom to build what I want, to build cars and to shoot guns in my backyard if I want.
Rural Arizona would be a step away from California in terms of dollar value, lower taxes, gas prices, vehicle registration fees, insurance and other things. Nothing is set in stone at this point. The future is still undetermined.