GetOutdoors takes trade-ins, but does not buy used kayaks. Try Craigslist or Facebook market pages to sell it. Local paddling clubs, as mentioned by Charles, is a great option as well.
There is a demand for kids boats try Tarheel paddlers on Facebook, gdi which is mostly a canoe group even Carolina Canoe Club 2 of the 3 are local clubs and most of the boaters do business with get outdoors. Get outdoors is a good company great people but by listing it on a club site you may do better. Great outdoor may take it as a trade in I just don't know about the buying outright
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