Similar to cars, some boats may hold their value better than others. Fishing boats and pontoon boats are likely to depreciate faster than other types of boats. Buying a used boat may offer consumers a better value as they should have already depreciated from their original purchase price. Within the first few years of ownership, you can expect a boat to depreciate the most. However, if you buy a used boat you may be able to avoid some depreciation. If you buy a used boat you should have it inspected or purchase it from a credible dealer. After about 7 to 10 years, a boat's depreciation should even out.