Kristoffer A. Diel SAMS® AMS® | Principal Marine Surveyor | (504) 236-8151 |

The Basics of a Pre-Purchase Marine Survey

A brief description of the basics of a pre-purchase survey, including responsibilities of the owner & the prospective buyer


  • The static in-the-water inspection must be first because it gives the Surveyor a good idea of the vessel’s condition and indicates whether it is safe to get underway.
  • The haul-out should be next for the same reason. It provides inspection of the underbody and underwater machinery.
  • The sea trial then takes place when the boat is back in the water and completes the survey.

The In-Water Inspection
A static in-the-water inspection covers most major systems and safety items. I insist that the Owner or their representative be present so they can turn systems on and off, and be available to answer questions. I recommend that the Prospective Buyer also attend. I begin the survey early in the day. At a reasonable hour of the morning, Owner and Prospective Buyer can arrive to activate the systems.

The Haul-Out
It is best to schedule the haul-out as the last thing before the yard personnel go to lunch. This is another “logistics” question that must be addressed when making arrangements for a survey. This provides a quiet hour for underwater machinery inspection.  If no serious problems are encountered, the vessel can then be re-launched and the sea trial undertaken.

The Sea Trial
During sea trial, the engine and overall vessel performance is evaluated. I inspect steering, controls, shafting, engine mounts and exhaust systems, as well as structural hull elements while under load. On sailboats, the overall sailing systems are examined and evaluated for condition and tuning.

It is critical that the vessel be properly prepared for survey. The survey’s quality can only be as good as the conditions under which it is conducted. All lockers must be empty of accumulated gear, and a thorough cleaning undertaken. A Surveyor will not move personal gear or accumulated dirt, but make a report note of “inaccessible.”

Click here to read Pre-Purchase Survey Logistics & Scheduling.