250 dealers???? How many of those dealers have a clue about custom built performance boats and their value??
How many of those dealers, brokers, surveyors have even sold, brokered or surveyed a used high performance boat??
How can they track the value of boats when only 5-10 of a model were produced in year and all the options vary so much that value varies by 30-50%??
They can't......they guess and depreciate them based on averages and percentages.