Engine and bottom maintenance is first and foremost. Nothing will sour a deal quicker than a potential buyer thinking, If the owner didn't spend the time or money to do the 1,000-hour service, what else hasn't he kept up with? Bottom and engine maintenance go hand in hand, especially during an engine survey, where sea trials reveal proper engine performance and verify the speeds advertised in the listing, both at cruise and top-end. Neglecting these items adds to the bottom line and is not factored in when making an offer to purchase. Basic maintenance is expected to be completed by the seller.