Boat maintenance is an important but not necessarily difficult part of boat ownership. Boat owners who ensure their boats are properly maintained can greatly reduce their risk of being stranded at sea while increasing their chances of having a great time out on the water.
The propeller should show no signs of damage. A damaged propeller can cause a host of problems, including stranding boaters on the water. Even if a damaged propeller doesn't strand a boat in the middle of the sea, it will likely tax the engine, which will decrease fuel efficiency.
It's also good to top off oil before heading out on the water and then checking oil levels upon one's return. Boats with 4-stroke motors consume very small amounts of oil, so if such boats are consuming large amounts of oil during each trip there's likely something wrong with the engine. A boat with a 2-stroke motor should maintain the same proportion between fuel and oil consumption. If the proportion starts changing dramatically, that's problematic.
Hull, Engine Cases
The boat hull and engine cases should be inspected for damage or signs of corrosion before heading out on the water. It's also a good idea to inspect the hull and engine when returning to the dock. This will save boaters the trouble of discovering problems on the next trip, which may put that trip in jeopardy.