I think that the single most important thing you can do by far is to invest in a plane ticket and spend some time in Belize (assuming you haven't already.) Although there's a lot of good information on Belize in books and on-line, nothing compares with actually being in Belize for a few weeks, seeing the actual situation and seeing how you respond to it. Of course try to sift through the vacation aspect of it, as any place looks different when you live there versus when you visit on vacation.
In my opinion, the best places to live in Belize are not the places you'd visit first on vacation, but then individual tastes vary.
I've written a couple of books on living/retiring/investing in Belize, one published by Avalon, Adapter Kit: Belize, and the other an eBook, Easy Belize, available on www.escapeartist.com
-- you might want to get a copy of one of those or the other book on the subject, Belize Retirement Guide by Bill & Claire Gray (not their real names.)
--Lan Sluder www.belizefirst.com