on a full disclosure basic, this is difficult to do as the yacht is being operated commercially and many rules apply, not to mention insurance costs etc. to be legal I suspect its a very expensive undertaking, and of course there is the issue of security of asset.
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On our recent path from New York City to the Chesapeake we spent some time with a couple from New Zealand who were saiing a catamaran on trade for the owner's use of their RV in New Zealand. I doubt if you would find an opportunity for such a long term trade, but if you have something to exchange, you might find a deal online.