About a half century ago, I saw an ad in the Buy& Sell paper for a "192? Martin guitar, worth $1000; asking price $200. Modernly decorated." A bit worried about what "Modernly decorated" meant, I hopped in my car and headed to Toronto to buy the guitar.

When I got there, I saw a guitar with beautiful slab-cut Brazilian back and sides and the ugliest paint job I'd ever seen on the front. It had once had a huge pick guard screwed to the front, but the holes were now filled with what looked like drywall mud. The bridge was not original and had been pulled off by the heavy guage strings that were on it. The photo below shows what someone who didn't know the value of this old O-21 did to it.

tragically modified Martin )-21 from the twenties
I offered the guy $50 for it and he said, "Yes," without taking a breath. I traded it and a bunch of other stuff and some cash for my 1962 D-21 about two weeks later.

The owner of the guitar shop, Ed Dick, told me that he had repaired the guitar and it was now owned by a musician, Wendy, who lived in B.C.
I sent her a photo of what the guitar looked like when I got it and she sent me back a current photo. She loves the guitar in its present condition.