This is somewhat old info and I'm not sure how helpful it is in light of the record guns sales earlier this year, but three years ago I traded a late 1970s M37 nickel airweight and a Taurus PT22 for a S&W 1917 at a LGS.
The nickel plating on the M37 had begun to discolor on the right side and the gun had been carried, so it had wear. I know it was shot, but I don't know how much or with what loads. A friend who could no longer use handguns because of a medical condition gave both the M37 and Taurus to me. I'm not fond of small handguns so I traded both. The M37 booked at about $350 at the time. The LGS put the M37 up for $400. He didn't have it long.