I had my US carrier unlock my phone (free), then bought a SIM card in Belize (~$25US). I buy pre-paid credit as needed, often on the days with double/triple credit. I can retrieve messages from my US phone if & when I want, and a select few people I give my Belizean number. It's the cheapest solution I've found. One little wrinkle: if the BZE phone is inactive for more than 3 months, the SIM card becomes useless. So, if I'm away longer than that I have someone top me up a little.