Check:
- HIN/registration ownership
- ABP and alterations since certification
- tube dents, cracks, corrosion and welds
- water inside tubes
- deck rot or composite delamination
- transom/engine pod
- steering
- fuel system
- electrical wiring
- battery installation
- rails and gates
- upholstery
- bimini and hardtop loads
- engine hours/service history
- prop/gearcase
- trailer ATM/GTM, brakes, tyres, bearings and width
Sea trial at loaded condition. Check acceleration, steering effort, ventilation/cavitation, spray, porpoising and deck vibration.
Inspect the structure, not the upholstery
Used pontoon boats present well. Furniture and canopies are easy to replace and easy to photograph, and they hide nothing about the parts that actually determine value: tubes, deck connection, transom and corrosion history.
Assume the boat has been used in the worst plausible way until the evidence says otherwise, and let the seller's records do the work of proving otherwise.
Structural checks
- Tubes: dents, deep scrapes, weld cracking, repairs, and any sign of water inside a chamber.
- Deck-to-tube connection: loose, missing or replaced fasteners, elongated holes, movement under load.
- Transom: cracking, distortion, evidence of over-powering or repeated impact.
- Underside of the deck where reachable, which is where neglect shows first.
- Corrosion at every point where dissimilar metals meet, especially stainless fittings on aluminium.
Paperwork checks
- Rating plate present and legible, and consistent with the engine fitted.
- Service history, particularly engine hours and any major work.
- Evidence of any modification and who assessed it.
- Registration status and that identifiers match the documents.
- Any outstanding finance against the vessel.
Sea trial
- Run it loaded, not empty, if that can be arranged.
- Check handling in a turn and the attitude at speed, and how it takes wake.
- Listen for movement or knocking between deck and tubes.
- Watch the trim: a boat that sits down at one corner is telling you something.
Where buyers go wrong
- Inspecting on the trailer only, so the waterline and running attitude are never seen.
- Accepting "it's always been in fresh water" without evidence.
- Valuing the fit-out and ignoring a tube repair.
- Skipping the paperwork check because the boat looks tidy.
Questions buyers ask
Is a water-filled tube fatal?
It is a serious finding that needs a proper assessment of cause and extent. It affects buoyancy distribution and points to a breach that will keep letting water in until it is fixed.
How much does saltwater history matter?
It matters most where dissimilar metals meet and where fresh-water rinsing was skipped. Ask how the boat was stored and rinsed, then verify by inspecting the fittings rather than the hull sides.