This is the most comprehensive type of inspection and is strongly advised when purchasing a new or used vessel.  It is used to ascertain the condition and the overall operation of the vessel.  The Survey will basically cover everything about the boat, which can be gleaned in a single day (sometimes 2 days, for large vessels). 

All visible and accessible areas of the hull will be examined, by hammer soundings, and by moisture meter readings as appropriate.  The survey includes such items as structural integrity, propulsion system, fuel system, electrical systems, navigation and miscellaneous on board systems, masts, rigging and sails, cosmetic appearance and overall maintenance.

It will not include intrusive procedures (such as destructive testing or stripping down engines), but the surveyor will get into every available nook and cranny, inspect all woodwork and fastenings, follow all hoses, pipes, wires and ropes to make full appraisal of the condition of the vessel and its systems.