Both the Baths and Spring Bay are national parks - only vendor at the baths (down on the beach) is Poor Man's bar (highly recommended) and at Spring Bay there are no vendors of any sort. Dive BVI has a small operation at Yacht Harbour and I suspect still rents some snorkeling equipment - are you on a cruise or staying on island? If the latter I would purchase on the mainland. Also there are better beaches for snorkeling on VG for example Mahoe Bay or Savannah bay.
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