I went through this process before, having kept 3 boats in the BVI for the past 15+ years.
You can create an IBC (international business corporation) in the BVI and register the
boat there. Calculate around $1000 per year in fees/costs for the BVI registry and business costs. This can be an advantage when it comes to inheritance
fees, as the transfer of
ownership occurs in a jurisdiction outside of your home country.
The BVI flag is a red ensign one, which is nice but not necessarily an advantage. Much depends upon your nationality and tax residence. Your plans for where you intend on keeping the boat also play a major role.
Last year I finally gave up on the BVI as my base (I'd been based at Nanny Cay on Tortola). The BVI costs have gone up significantly, new
fees and
taxes magically appear every year and the belongers are noticeably more hostile towards outsiders. So I moved my base of operations further south and haven't missed the BVI at all (apart from losing touch with my old friends and contacts).
If you buy through a
broker, they can easily convert the BVI-flagged boat to a US-Registered one. They can do that in their sleep! I can't think of any disadvantages to doing that, if you continue to keep your boat in the BVI the only difference in cost would be that you would need to do annual "temporary import" at around $200.