And remember WIFI is not as "free" as it is in the US. A lot of cafes/bars offer it if you are a paying customer, and some of the bigger hotels. But the speed will likely be low for video chat. I agree that a rented phone or an unlocked phone with local SIM is a good way to go for regular phone contact, but if you really need video chat WIFI/3G is not going to cut it in Belize.
Thanks for the tag team GG;
MMM my bad the Nokia I spoke of is the 1661. As I said they are nothing special they do allow SMS & they work just fine. They get a lower reviews due to people wanting more on a cell. But all will admit they work fine as your basic unlocked GSM travel phone. New 39US on Amazon, theyre less at WalMart WalMart Nokia 1661
If you want to go the unlock, trim the sim, route (hassle IMHO) it will work but I prefer not to monkey with my main cell when for less than $50 US your up and running with a local phone #
If you do use the alterante route, I would be very cautious about the data rate aspects of your phone. Foreign data rates from AT&T for example are like fifty cents per Kb, yes I said Kb.
Belize does not offer reciprocal rates like many other countries do so long disatnce rates stay high if you use your own domestic provider. Just another reason I prefer the local phone. 60 cents per minut to the US vs like 3 dollars /minute. Check with your provider. Also they may actually give you an unlock code if you ask and explain you are traveling abroad. Maybe, maybe not.
Your other option as Changosgal offers is to rent locally, but I think those run like 10US per day. Ask, I'm not sure of current rates.