Like many well seasoned SXM travelers, I highly recommend Kenny's Car Rental.
Lesley Bruce (owner) is well respected for his friendly service, very reliable cars, competitive prices, flexibility with flight arrivals/delays and absolutely no hassels.
Another advantage is he meets you at the airport with the car. No need to take a shuttle off-site. Paperwork is completed in the airport parking lot and Lesley has you on your way in 10 to 15 minutes.
Contact Kenny's Car Rental at
bruce@sintmaarten.net.