I know of at least two services in the UK, Heritage Guns (Toby Barclay) and Vintage Guns (Diggory Haddoke)who will, for a modest and fair fee, view guns at auction and deliver a full report via email before the auction. I've gotten one of these myself, and the information is full and complete, lacking only an internal inspection, which wouldn't be possible. However it does include vital information relating to the barrels etc. They will also offer their subjective judgement on the overall appeal of the gun, and give an idea of any renovation or restoration cost. I can't imagine tendering a bid based on a photo or description in the auction catalogue without an exam by one of these gentlemen. They have been used by friends as well, and it's a very inexpensive way to avoid a very expensive mistake.
