Buyer's guide
DIY Boat Inspection Checklist
Filter out bad boats in 30 minutes — before you pay a surveyor $400 to tell you what you could have seen yourself.
A pre-purchase inspection by a marine surveyor runs $20–$25 per foot. Worth it on a boat you're serious about — but a waste on one with obvious problems you could spot in the parking lot. Bring this checklist, a flashlight, and a screwdriver. If the boat fails three or more items, walk.
1. Hull integrity (15 min)
Most expensive surprises live below the waterline. Walk around the boat slowly and run a flat palm across every surface.
- Spider cracks on the gelcoat — stars or radiating lines hint at impact damage.
- Soft spots on the deck or transom — tap with a coin; a dull thud signals delamination.
- Blistering or 'pox' along the bottom — common on boats stored in the water year-round.
- Hairline cracks at the chine or keel — usually trailer-bunk impact; check for matching cracks inside.
- Through-hulls (drains, transducers, livewell) — silicone smears mean someone chased a leak.
- Stringers under the deck plate — push hard; movement or rot is a deal-breaker.
2. Engine and fluids (10 min)
You can't run a compression test in 10 minutes, but you can spot a neglected powerhead.
- Pull the dipstick — milky oil means water in the crankcase; metallic flake means bearing wear.
- Gear-case oil (lower unit) — same test; milky = blown seal, $800–$2,500 repair.
- Cowling interior — heavy salt crust = no freshwater flush, accelerated corrosion.
- Spark plugs (if accessible) — uniform tan is healthy; black or oily plugs are a red flag.
- Belt and hoses — cracks, glaze, or soft spots mean overdue service.
- Hour meter vs. listing — confirm hours match and ask for service records since the last 100-hour interval.
3. Electrical basics (5 min)
Intermittent electronics on a used boat are almost always grounding or battery issues — easy to spot, painful to chase later.
- Battery terminals — pitting or verdigris means the seller skipped basic maintenance.
- Ground straps — should be tight, clean, and corrosion-free.
- Wire bundles — heat-shrink and zip-ties = ok; electrical tape and butt-splices = redo it all.
- Power up every electronic at once — chartplotter, VHF, stereo, livewell. Voltage sag or resets mean wiring problems.
- Bilge pump — flip the float; pump should run dry without a burning smell.
4. Safety gear and paperwork
Missing safety gear is cheap to fix but tells you how the boat was used. Missing paperwork can sink the deal entirely.
- PFDs — one wearable per passenger, current and not mildewed.
- Fire extinguisher — check the gauge and tag date.
- Flares and visual signals — within expiration.
- Title and registration — names match the seller's ID; no liens.
- Hull Identification Number (HIN) — physically matches the title and the registration.
- Maintenance log — any seller who can't produce one has either lost it or never kept one.
Skip the parking-lot inspection.
Paste the listing into HullCheck and get a mechanic-grade report, fair-value range, and negotiation script in under a minute — before you even drive out to see the boat.
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