Based on your location in Abaco, I know you do have some tough conditions. We spend Feb every year in Treasure Cay, a great place.
If you plan to actually work on the base limestone get a larger
TLB Kub L35 or L48 or JD 110 series that you can attach a hydralic hammer to the BH. These will run $32-50K range new pending options.
If you don't require a hammer attachment go with the B21 series
TLB from Kubota. These are tough commercial units that don't break the bank to buy new ($25K), as well they last a long time with minimal repairs. If you can find a good one used great, but they are tough to find. Also pending the size truck/trailer you have, you might find the bigger units too much to haul.
So if you can buy new, I would advise that since parts and repair availabilty in your location may put you down for a few days.
good luck,
Carl