If you're full time, you need a domicile, a real street address, and/or mail services. Escapees is the one! The have tons of how-to pages to get everything set up! They have an add-on service where you can selectively have pieces of mail scanned and be available on your account page on-line -- huge benefit for those of us traveling a lot!
They are also a great RV club in general with many discounts, eductional writeups, and a great community of RV'ers! The also have a top-notch roadside assistance program.
Some benefits of domiciling in Texas, Polk County:
Extremely fulltimer RV friendly
No state income tax
The court system is understanding. I was called for jury duty a few times. I was far from Texas. Just a call to the office, and I was deferred - no issues.
No justification needed for absentee voting ballot
DMV is FAST - had our drivers licenses and registrations transfered in less than 30 minutes.
Simple phone call if unable to go in for inspection upon registration renewals and will mail stickers!
Winnebago Parts Lookup
Largest Winnebago Dealership in America. Lichtsinn RV has the service and parts for pretty much everything for our RVs! They also have a pretty good video "Hot To" library.
Brian (RV with TITO) shows a unique way to install solar panels on your RV roof WITHOUT screws! Using the Superstrut channels provides a very flexible solution to mounting the panels with just VHB Tape!
If you're serious about having Internet on the road, Technomadia has a ton of extremely useful information. Be sure to join their Aficionados group for direct help in finding solutions, getting the right plans, etc.