Hey all,
Here's an update. Based on your responses, it became clear that the lack of bottom paint refresh doesn't affect blistering, that simply comes down to time in the water, quality of laminate construction and if there is a barrier coat. On the lake where the boat is, there are no haulout facilities, so basically no one has their boat hauled out of the water for any kind of below-waterline maintenance. I went ahead with the survey and although the surveyor couldn't examine the underside, he did reach under water and feel along the hull as best he could, and noticed 1) it was very dirty and 2) there definitely were blisters. However, there were some other things wrong with the boat too above the waterline - diesel was sorely in need of maintenance, there were some leaks (or had been), a large portion of the cabin topside surface was "wet" (water-soaked), and a few other things that indicated that someone did the "fun" part of owning a boat but didn't do much on the hard part (maintenance). So I'm either going to ask for a large price reduction or walk away, not even sure a large price reduction would compensate for what kind of problems the bottom might have given the condition of the top. This is a really good example of why one just about must hire a surveyor - one can clean up the inside of a boat well enough to make internet pictures look great, but it's things like picking up bilge covers and looking inside where the true problems manifest where you won't see online, and the owner/broker sure isn't going to tell you voluntarily.
I fully expect the broker, as nice as he is, to dispute the results of the survey. Sellers seem to like to tell buyers that "most surveyors don't know what they're doing." Yet if the surveyor didn't find anything wrong with the boat, I doubt the owners would tell you in that case the surveyor didn't know what they were doing.
Anyway. I don't expect them to come off as much as I need to handle the required repairs plus other general unknowns given the now-known-knowns, so this is probably the end of this lead. Sad, Hunter 33.5's in the 89-90 year are rare, especially ones within 1,000 miles of where I live, but bad idea to pick up one which seems like it may have been rode hard and put away wet.
Thanks everyone for the great input, and I hope this thread helps others.
'Dubs