Re: 30 amp hookup ?and mail address on the rd.?
First of all, I would suggest that you check out Escapees RV Club in Texas because they are the only complete support organization for fulltimers that exists. We have been using their service as our address now for more than 8 1/2 years and love what they offer. It is far more than just a simple mail service. Check them out at
www.escapees.com
Next, I tend to favor Texas, but there are three states that tend to be favored by most. They are Texas, Florida and South Dakota. Each has it's strong points and it's weaker ones. Part of the question of legal domicile is that you are supposed to have the intent to return to your place of domicile when your travels are over. It sounds as though Texas might be that place, but............ None of those three states have any state income tax, and none require you to live in the state for any period of time. Sales tax favors SD at 3% and Texas has the best health insurance coverage. Jury service is easy if you choose Escapees in Texas. Winters would favor Florida, then Texas.
I suggest that you need to get a book or two on this life and read them before you get too far. Also, if you have not traveled by RV, you would be smart to rent one for a trip of a couple of weeks or so first, just to be sure that you like the style of travel.
The amount of power that you will need depends upon the number of air conditioners that you have, and the amount of power that you use. If you have only one air conditioner, 30A is probably enough. We have 50A but we also have and use two air conditioners as well as lots of other electrical toys.
Make sure that you have an RV that will carry the weight of the things that you wish to carry with you, safely. And then make sure that you choose a tow vehicle that will deal with the weight of the trailer. Weight limits are designed into every tow vehicle and every RV. Learn what they are and stay within them.