The marine survey is the most important step in buying a boat. It's your objective look at what you're actually buying, distinct from the glossy listing photos and the broker's sales pitch. Here's how to get the most out of it.
A pre-purchase survey covers: hull condition (above and below waterline), deck and structural integrity, engine and mechanical systems, electrical systems, plumbing and through-hulls, safety equipment, navigation electronics, and general condition.
The surveyor uses moisture meters, sounding hammers (tap testing for delamination), and visual inspection. They'll check every through-hull, open every hatch, and test every system they can access.
What they won't do: they don't tear apart the boat, dive underneath, or disassemble engines. If they suspect a hidden problem, they'll recommend further investigation by a specialist.
Pre-purchase survey: the full inspection for buyers. This is what your lender and insurer require. Cost: $15-30/ft.
Insurance/condition survey: a periodic check for your insurance company, typically required every 5-10 years. Shorter and less expensive.
Damage survey: after a grounding, collision, or storm. Documents the damage for insurance claims.
Engine survey: a separate specialist inspection of engines and mechanical systems. Recommended for boats with high-value engines or high hours. Your marine surveyor may recommend this.
Survey reports list findings by severity. The key categories are: safety recommendations (must fix), significant findings (should fix), maintenance items (plan to fix), and observations (informational).
Don't panic at the length. A 40-page survey report on a 20-year-old boat is normal. What matters is the safety section and the significant findings. Everything else is expected wear and context.
Look for: water intrusion in the hull or deck core, structural issues (stringer damage, transom softness), engine condition relative to hours, and the overall maintenance trajectory (improving or declining?).
Red flags: soft transom, water in fuel tanks, significant hull blistering, corroded through-hulls, non-functional bilge pumps, outdated fire suppression, cracked exhaust risers on gas engines, and any structural compromise.
Normal findings: minor gelcoat cracks, cosmetic wear, minor corrosion on hardware, some moisture readings in non-critical areas, age-appropriate systems that still function. Every used boat has these.
The question isn't whether there are findings - there always are. The question is whether the findings match the price. A $50,000 boat with $5,000 in findings is normal. A $50,000 boat with $30,000 in findings is a different conversation.
Total up the cost of significant findings and safety items. Present this to the seller as a request for either: a price reduction, seller-completed repairs, or an escrow holdback.
Most sellers expect 3-8% off the agreed price after survey. If the findings total more than 15-20% of the price, the boat may not be worth pursuing at any realistic discount.
Get repair estimates in writing from qualified marine service providers, not from online searches. Sellers take documented repair quotes more seriously than round numbers.
Informed Boating's survey center helps you prepare checklists, store findings, and negotiate with data. Start free.
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