Have found a 2003 18' aluminum boat with a Merc 135 that has 78 hours on it for less than $4k. Being that I know next to nothing about boats, what key questions should I be asking? When going to look at the boat in person, what key things should I be looking at? Is it unreasonable to request a test drive at this pricepoint? Should I be satisfied with just having it just run with earmuffs on or should I have it inspected by a marina?