The haul-out is the second of the three parts of a pre-purchase survey that BoatUS lists, between the in-water survey and the trial run. The yard lifts the boat in a travel hoist and holds it in the slings or blocks it ashore for a few hours. The buyer usually books and pays the yard.
It's the only time the surveyor sees the underwater hull and everything fitted to it.
What a surveyor checks
The bottom for blisters, cracks, damage and repairs, sounded with a hammer and read with a moisture meter. The keel joint and rudder. The propeller, shaft and cutless bearing shaken for play. Every through-hull from outside, and the anodes.
Timing matters for the readings. A hull straight out of the water reads wet. Tramex says to test once it's washed and dry, and notes some hulls read high for weeks after lifting, so many surveyors ask the yard to lift early in the day.
In the report
Say when the boat was lifted and when readings were taken, and list the underwater findings by system. See the out of water survey report template.