Immigration will involve a relatively simple once a month process, just a trip to your local Immigration office for a usually quick interview with an Immigration official. Approval is a stamp in your passport that grants you an additional 30 days in Belize. Cost is $200 BZ each time.
Once you have legally resided in Belize for one year, you may apply for Permanent Residency. This will cease the monthly trips to Immigration as you will be recognized as a resident.
After five years, you will be able to apply for citizenship and a Belize passport. Belize is part of CARICOM (the Caribbean Community) which is comprised of fifteen Caribbean nations. A Caribbean passport will connect you with each of these countries if you wish to travel out from Belize.