I've been domiciled in SD for 8 yrs, with Americas Mailbox. Its really a simple process. Sign up for your new address, transfer all your accounts, insurance & official correspondence to that address. You can have the mail forwarding agency transfer your vehicle registrations ahead of time (with a notorized power of attorney) or you can wait until your in person visit to do the vehicle registrations at the same time you do the drivers license. All it takes is a one day & one overnight visit in person, the rest can be done remotely/electronically. The most difficult part is gathering all the documents needed to prove your identity to the DMV as required for the "Real ID" compliant drivers license. Especially ladies who have gone through name changes, need to show the original, official marriage & divorce papers, as well as certified birth certificates or passport, etc. http://www.americas-mailbox.com/home/tips/drivers-license
The only negative to SD, is the lack of private medical insurance with national coverage, for those under 65. For those over 65 there is no problem using SD for Medicare & Medicare supplements. I can't comment on Medicare Advantage Plans since those are also private insurance and controlled by the issuing company.
While you're going through all the address change notifications, do yourself a favor and convert everything possible to online electronic access, electronic statements, electronic payments, direct deposit, etc. the less hard copy documents you get mailed, the better. With almost everything available online in electronic form, do you really want to pay extra postage to re-mail heavy, hard copies of newsletters & magazines, etc.
Don't forget the most important part of changing your domicile state, cutting ties to your old state and physically moving out of that state. Getting a new mailing address doesn't trigger the change; moving out of the old state is what triggers the change.
