Most visitors find it unnecessary to rent a car, as roads are atrocious. Those wanting to see more of the island might consider a taxi guide. Before going to your hotel, drop in at the Tourist Information Centre and ask for a driver who's familiar with the attractions of the island (all of them are). You should negotiate the fare in advance. Rental cars, owned by locals, are available at the port, or you can hire a taxi at the dock to take you around the island or to your hotel. Taxis are reasonably priced, but an even better bet are the so-called dollar cabs, which take you anywhere on the island for a small fee. They don't seem to have a regular schedule -- you just flag one down.
Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.