Dawnp, GlennA makes good recommendations, a few years ago we wanted to take my daughter and 3 other graduating HS seniors on a trip, but we figured it best to let someone else do the driving. Captain Jim on BlueMoon was a great choice for us, the girls had a blast. I wrote a looong trip report here on TTOL with photo's if you want to read it.
Chartering a bareboat mono/cat and hiring a captain is another option, check out all of the websites Moorings, Sunsail,CYOA, TMM, BVIYC, Conch, Footloose etc etc. Check out the availability of a 3 cabin mono or cat that fits your budget, then add in approx. $200 per day for a captain. Send your online requests directly to the charter companies and you'll get a quick detailed cost estimate, if you've never chartered before you'll be surprised by some of the added fees.
when do you plan to charter? <img src="http://www.traveltalkonline.com/forums/images/graemlins/Cheers.gif" alt="" />