I believe the fare currently is $169 each way per person plus int'l processing fees of $60pp each way (COVID protocol rates), 5 person minimum. I think you have will have to clear in to the territory thru Road Town. That may change by October if they open up West End for entry. Heading back to USVI, I believe they can pick you up at West End, clear in to US at St. John (Cruz Bay) and then on to Red Hook, St. Thomas. Go on their web site and hit up the live chat. You can also try Island Time Water Taxi. They are BVI based and I believe a little cheaper. We are using them for a July trip.
Hope that helps.
Cheers.