"Residence" is in the eye of the resident. That is to say, you can declare yourself to be a resident of practically anywhere. That won't let you work there, or even go there without a visa, but it doesn't stop you from declaring it to people like insurance companies. To be on the safe side, I'd recommend you stick to countries where you're either a citizen or have official Resident status.
The only problem with having no residence is that insurance companies and such require a street address for your residency. When we first applied for boat insurance, the company insisted on a street address, which of course we didn't have. We called them and the Customer Service
Rep said, "Well, where are you right now?" We told them where we were anchored for the night and she said, "So, give that address." We did, and no further problems ...
until they wanted to mail something to us. Most insurance brokers (such as our current
one, Al Golden, email@example.com
) will happily scan and e-mail anything you need, like the policy; but they also want to send it somewhere by mail. Most full-time cruisers have a mail drop somewhere, such as St. Brendan's in Florida
, USA. We have a very long-suffering friend who lets us use her home address. She throws away all the junk and tells us about the rest. Urgent stuff, she scans and e-mails; less urgent, she saves until we fly back to the States or a friend comes to visit us. We highly recommend this approach!
Anyway, time to declare yourself a resident of your favorite country. Good luck!