Flying through St. Thomas would require an overnight for us, so we only fly to Tortola. There is a departure fee on ferries from the US, the ferries charge for bags and Tortola taxis are expensive. Add it all up and it would take us an extra day and not save money.
InterCaribbean has a terrible reputation due to cancelled and delayed flights, so we do not fly them. We don't fly Spirit either, and might fly Frontier if they had the only direct flights to a destination. I am not aware that those three airlines codeshare, so miss a flight and you have to buy new tickets.
Your best bet is American through Miami to Beef. Another option is Delta to San Juan and connect on Cape Air or Tradewinds. Or charter a plane if your group is large enough.
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