Makes for interesting conversation. If I refer to the most commonly used insurance estimating software they only reference small non-motorized water craft like a stealth skiff. They apply a depreciation rate of 10% per year. If the boat is still serviceable at 10 years most adjusters would probably value the boat at 65%. So much depends on make and style. If the boat is an unpopular maker or hull design you will have trouble giving it away at 10 years old. 1994 OMC Bass Boats such as Stratos, Hydrosport etc. originally sold for $12,000 to $15,000 are on the market now for $4,000 to $5,000. A Ranger bass boat that age will sell for twice that amount. The Lund and Alumacraft Duckers are selling for $900 to $1,500. I suspect they sold for less than $500 when new. I would check the internet for comprables in your area. Good Luck
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