By way of update, the owner was confident his Baltic 37 had been improperly reported and ponied up for keel inspection and half the haul-out. I hired a certified surveyor I had used before, and he found low moisture in the hull, no signs of osmosis (and a good
epoxy treatment from a few years back), no underwater damage or repairs, and no sign of water ingress in the decks (but noting they needed to be tended to asap). There were a range of smaller issues, and I ended up deciding to buy her. I have also had some great private advice and suggestions from other Baltic owners (contacted through this and other boards). The owner has also been helpful, and is leaving her clean and organized.
I'll have a busy winter, but look forward to sailing her in the spring.
Regards and thanks,
Chris