Boat value according to what? You did not say how you arrived at $300K as the "value" of these things, so immediately I'm going to pick on that until my hunch proves otherwise.
Lots of people think that services such as NADA can provide them with the boats value. Lots of people are also wrong. That's not quite just a random opinion either, its a provable fact if you have access to the number of samples a set of data is based upon. It's a fact based on a simple principles of statistics. Years ago a fellow who was with a firm getting out of the boat data business who had tried to market to buyers/sellers clued me in. He actually sent me on CD their database at the time to prove his point, which was essentially this. Boats inherently are too different, and not numerous enough. If you think about how few boats are produced of any one model, how different two "identical" boats can be value wise and the scarcity of specimens being sold, you will start getting the point. In many many cases, the calculated value is going to be based on single digits by the time you get to the right make/year of boat, and that's not even considering geography which can have a pretty big impact. If your comparing something for which a lot of specimens were produced, then maybe. For everything else, its abstracted. Just as a reference point, in some of the work I do we typically won't allow someone to view satisfaction results unless the number of responses is greater than 50 or 100 depending on the question as we have found that we can not train people to make appropriate decisions below this level of responses. If we were looking at cars getting 50 comparable would be easy, for boats its a pretty rare day to see that many like comparables of a single brand let alone a specific model. Often you have single digits. It's just math problem. Plus even if you did, they are all too different anyway.
Boats are much more like houses. They require examination of the specific vessel, then comps based on similar vessels. That's why you pay for condition and valuation surveys for both loans and insurance. Nada is useful for someone like an adjuster who is making generalizations across a very broad range of vessels. Its useless for individuals and "most" specific models. That data may still be useful if I'm an insurer, even at the wide level of confidence, so again NADA and other guides serve a purpose, just not for an individual buyer/seller.
So with that long diatribe i've copied from memory over and over for more than a decade
Tell us again, exactly how did you arrive at the vessels value?