Road Town has the largest charter companies, but there are scores of others on every island. A proficiency test is required before you're allowed to go it alone and night sailing or sailing near Anegada, where waters can be very rough, are prohibited. Crewed yachts are also for hire. Fly BVI flies between the islands of Tortola and Virgin Gorda, with occasional flights to Anegada, as well. A better way to island-hop in the British Virgins is by ferry, which go between the larger islands of Tortola, Virgin Gorda and Jost Van Dyke.
Ferries make less frequent trips to the archipelago's smaller islands.
Dozens of water taxis are available to ferry you anywhere else you may wish to go. There are major international car rental agencies on Tortola. You'll need a temporary British Virgin Islands driving license, available from the rental agencies, and a valid license from home. Drive on the left. Anegada has a jeep rental shop, which is good because its roads are nothing more than glorified sandlots.