First you will need to decide how you want to live , then try to decide where.
Every state has a need for a certain amount of money to function, and then some determine they want a lot of extra stuff that forces that number higher.
If you don't care for the arts, cost associated with them are unacceptable to you. The same can be said for all services above what a locality considers a bare minimum.
Taxes vary widely and something younger folks don't consider is that some areas have substantial breaks for seniors.
Myself, I have decided to look for low taxes, small town setting with medical college or university within 50 miles, avg summer high in low to mid 80's, avg winter lows in high 30's and snowfall under 18".
I don't want nightlife, like quiet, refuse to consider public transportation, and generally want to be left alone by government.
If you are going mobile for a couple of years to find that spot, check with an outfit like
https://www.escapees.com/
Setting domicile, mail services and the like are all covered and they have material there to explain.
Also select a state for your mobile time that simplify's registration and inspection requirements unless you are certain you will be going back there every year to get a safety or smog check, some states don't require those.
You have a ton of possibilities to consider, enjoy the journey.