Also be cautious about which agency needs what documentation!
Last year on my way back to the states to get my dog, I stopped by the airport animal immigration section to make sure they had all of my approvals from BAHA (I couldn't seem to get the faxed approvals from directly). They did but could not give me a copy of the paperwork (said I would not need it as they were the approving authority).
However, American Airlines would not allow my dog to travel without the BAHA paperwork and were delayed (I will skip the drama that followed) until the employees in Belize presented to work, answer the phone and fax the documents (AA refused to accept a verbal approval from them) long distance (which I agreed to pay). What a fiasco! I am still not sure who was right about what, however, I would suggest getting the approvals in hand prior to travel.