Buying a boat - this can't be right, can it??

[Lakesailor]

All those who say buyer should try similar boat first and gather info beforehand, make his mind etc - well, that may be right with buying a popular dinghy...
My boat is one of 20 ever built - where do I find another to try?

Absolutely, why should someone else allow the prospective buyer to try their boat. The only person who would benefit would be the vendor. So it should be their boat that is the demonstrator.
All this talk of time-wasters/tyre-kickers etc is coming from the perspective of people who have put themselves out and didn't make a sale. Tough. That's how it works. No one has suggested you should toss the keys over and hope they don't wreck it. If you want you £30k or £150K do a bit of work yourself and sell the boat.

 

[Rossynant]

Maybe I should add that I contacted Owners Club and was offered a ride by someone? But not on same model, nevertheless similar so it would be a great help for someone; for me it was not so much important. Also was given contact to owner of identical boat, but it happened to be stored ashore. Also got any info possible on boat, but could not find those important details that interested me most.

So it's good advice for OP to do his homework, but I guess he has done this already.

As said best thing is to discuss matters more with a broker. There may be valid reason for not taking this boat out, it sounds this way. But some arrangement can be made, I'm sure, for OP to get general idea of boat state.
What is important here - the practice of refunding the deposit only if survey shows something serious. It should be refundable in any case buyer walks away, as the real purpose for it is to cover costs or losses if some happen, and showing buyer commitment - not only for case where survey finds "serious issues". Buyers may be satisfied first that probability he don't want the boat is small.
If there are issues making boat unseaworthy then it should not be put for sale! Or at least advertised correctly - with those issues clearly stated, or described as "for rebuilding"

Survey is no guarantee of anything. I had a good surveyor. I spent whole day later going over boat again. We both missed few really important problems... Not a big deal, but such that should be repaired before going to sea.