its not the surveyors primary or secondary job to put a "value" on a boat.
The surveyor will inspect the craft for condition and "seaworthyness" (did I just write "seaworthyness"?)
Most of the guide values are not worth the internet time to do. You can't plug in the various factors to get a good determination. I've seen them very high, and also, very low.
As an aside, a surveyor may include sale prices of other boats in the same catagory, but, IMHO, these are worthless. The "selling price" of a boat has many determining factors, equipment level, condition, economic constraints all must be taken into account...
I can see it now... fred wants a frogbobber 41 for 139k, the surveyor says, "its worth about 135k", fred cuts a check... 3 months later, while fred and his comely wife matilda are sharing a merlot at the dock with the neighbors, fred is told "you could have got that boat for 70k, because the owner was in serious financial trouble, and their kid used it as a floating meth lab"
hey, you only wanted the surveyor to "take a quick look".
Do your own research, ask around, spend some time looking... it will serve you well.
We are not primarily on earth to see through one another, but to see one another through
Some people are like slinkies: not really good for anything... but you can't help laughing when you push them down the stairs