US currency can be used at the rate of two Barbados dollars for one US dollar. There are plenty of ATM machines all over the island (including in the departure area of the airport) that have access to the major banks in North America. All major US and Canadian bank cards work fine.
Bring mosquito repellant. There are (infrequent) outbreaks of dengue fever and (more recently) chikungunya, so check ahead of time. In the recent past, neither has been a problem. Very recently, there have been reported Zika virus infections. Zika infections are usually mild, but pregnant women should be aware that they are linked to birth defects (microcephalitis).
For up-to-date information about security and health in Barbados, consult the Government of Canada Barbados Travel Advisories.
There are computers on campus with access to the internet. Bellairs is fully covered by a wireless network called Bellairs or Bellair's. There is a 15USD (weekly) charge for the use of this network.
Food is not included in the room rates.
Finally, this document (PDF) contains a description of the house rules of the Institute.