How to Choose a Marine Surveyor

Don't buy a used boat without a survey. A surveyor spends four to six hours going over the hull, engine, electrical, and rigging. They find blisters, soft spots, corroded wiring, and problems that aren't obvious from a sea trial. The survey costs $15 to $25 per foot. On a 30-footer, that's $450 to $750 to avoid a $15,000 mistake.

What a survey covers

A standard pre-purchase survey is a visual and tactile inspection of the entire boat. The surveyor taps the hull with a hammer to find delamination, checks the stringers and transom for rot, inspects all through-hulls and seacocks, tests the steering and controls, and goes through the electrical system looking for corroded connections, undersized wiring, and code violations.

The engine gets a compression test and an inspection of hoses, belts, mounts, and exhaust. The surveyor runs the boat if possible, checking RPM at wide-open throttle against the manufacturer's spec. A motor that can't reach rated RPM usually has a prop problem, but sometimes it's something worse.

You get a written report, usually 15 to 40 pages, with photos. The report lists every deficiency and rates them by severity. Your insurance company will want a copy. Your lender probably will too.

Types of surveys

What certifications matter

Look for SAMS (Society of Accredited Marine Surveyors) or NAMS (National Association of Marine Surveyors) accreditation. Both organizations require experience, continuing education, and adherence to standards of practice. An accredited surveyor has done at least 200 to 400 surveys under supervision before getting their credential.

ABYC (American Boat and Yacht Council) certification is a bonus. It means the surveyor knows the current electrical and systems standards, which matters when evaluating wiring and fuel systems.

Someone without accreditation might be fine if they have decades of boatyard experience, but you're taking a risk. Insurance companies sometimes reject surveys from non-accredited surveyors.

How to find a good surveyor

Start with the SAMS or NAMS directory. Filter by your area and the type of boat you're buying. A surveyor who specializes in sailboats might miss things on a sportfish, and vice versa. Ask what types of boats they inspect most often.

Get references. Talk to the last two or three buyers they worked for. Ask if the surveyor found things the buyer didn't expect, and whether the report was detailed enough to negotiate on price or get repairs done.

Don't use a surveyor recommended by the seller or the seller's broker. There's no rule against it, but the incentive structure is wrong. You want someone whose only obligation is to you.

What a survey won't tell you

Surveys are visual inspections. The surveyor doesn't pull engines, open sealed compartments, or destructively test anything. They can't see inside a fuel tank, behind a headliner, or under a glassed-over repair. A boat can pass a survey and still have hidden problems.

If the surveyor flags something but can't determine the extent of the damage, they'll recommend further investigation by a specialist. That's not a cop-out. It means you should get a diesel mechanic, electrician, or fiberglass specialist to take a closer look before you buy.