I can highly recommend a tour company, Thenford Grey Tours
http://www.thenfordgreytours.com/. Mr. Grey is a local entrepeneur that maintains a modern fleet of vehicles and offers several excursions at reasonable prices. You cannot book through the ship. Secure your reservation through the website, there is no deposit required. Also, read the reviews of this company on Tripadvisor, all very positive. We did the "Grand Tour of St. Kitts" which was fun. They also offer beach days for around $25pp, which is very reasonable.
