Bareboat in the BVI
We've chartered Moorings, Barecat and Conch. Big differences in the boats and prices. The Moorings boat was like new and the price was high. Barecats had lower prices but nice boats. Conch is the bottom on price and old boats BUT... I could not complain about the value received, it was a good deal on an old boat but the same BVI's you get with anyone. Check TMM. They have been around a long time.
I'd also suggest checking the USVI as a start. Easy to get to and easier to provision but still only a day away from Jost. Don't count St. john out either. They have installed mooring balls in many of the bays so you might find more more secluded anchorages there than you think on your way to the BVI.
One comment on Sunsail, my pet peeve with them. Your charter begins at 6 pm. It isn't likely you will go any where at that time of day so I've always considered a Sunsail week as 6 days with a sleepaboard, not a full week.