The bank reference letter must be an original, not a fax or photocopy.
The letter should state that you have been a customer for X number of years and that you are a client in good standing.
There is no need for your bank to include any deposit references. ie. How much money you have in the bank.
The references are required so that if you turn out to be a bad guy the banks in Belize did try to verify who you were prior to opening the account and will have a US bank reference to back up their defence.
You do not have to be a resident (therefore you can be a tourist) in order to open a bank account. However be aware that your Belize bank account will most likely be maintained in Belize dollars. You can arrange with your bank at home to automatically wire a certain amount to your account monthly so you don't have to worry about using atms and a bank card (with all those additional fees.) Here in Belize it is not normal to use a bank card to buy small amount of groceries etc. In fact most stores that take credit/debit cards have a minimum purchase amount before they will accept your card.
You might not be able to qualify for a Visa credit card until you are an official resident of Belize. You used to be able to but it has become more difficult because of the lack of foreign exchange dollars here in Belize. Your credit card needs to be paid in US dollars and you require an exchange control permit each time you pay your card and I guess you need to have a fixed Belize address in order to receive the permit...... I don't know why it is so difficult, but it is.
There is a branch of Scotia Bank here - which I believe is still a Canandian Bank???? You may be able to maintain your account here linked to your account in Canada.