If you're not expecting a local buyer, locate the boat in a strong boating market, with lots of brokers, and easy to commercially fly or drive to. One of the things to consider is that your boat (anyone's boat) may not be the first boat on a buyer's list to look at. If the boat is in a less busy boat buying and selling area, it becomes a destination trip. You might get 2 or 3 times as many people coming to view your boat while they are looking at others. Also, I would think that locating your boat with others of similar type would be beneficial. If you were trying to sell a offshore sport fishing boat, putting it in a sailboat brokerage probably doesn't make sense.
Ted