If moving and living in Belize is totally dependent on paid employment when you arrive it is going to be really difficult.
Employment in Belize for expats is rare to find, unless you have skills needed but unavailable in Belize. You need a work permit not always granted and can take months to years to be approved. Jobs are always offered to local persons before expats are considered. Salary levels in Belize are really low, they do have minimum wage levels which depending on type of work start at $3 bze per hour for an adult. Under 21 is $2 an hour. $2 bze is $! us.
If you have some cash behind you you could start your own business and Hvac might not be a bad business to start.
Without the cash behind you Belize is not as inexpensive as you probably imagine. I am not just trying to pour cold water on your dream but being a realist.
We came to the states for our last adventure before we die but as we didn't die yet, there is time for another adventure this time back to Belize.