We purchased our Dufour 455GL through A&C Yacht brokers. Our experience with Michel was absolutely first class. He was incredibly helpful at every stage of the process and he was a great help even after we had purchased Mojito. He was under no obligation to help after the contract was signed but he helped source the parts and labour that we needed for a whole month after the contract was signed and the boat paid for.
If you are going to buy or sell a yacht in Martinique I would recommend A&C without any hesitation. We had used another broker in Le Marin and had a very bad experience so be careful who you use.