actually two mistakes in 25 years.
My dad bought me a Colt OACP in 1988 when I graduated the police academy. I did alot of garage stuff to it that I could not return to original. Only cosmetic and to the untrained eye, you would never see it.
The gun was with me alot in the early days but toward late 90s, I wanted something else... and my dad suggested I sell the COACP. Well I did but when he passed in 2005......I wanted the gun back.
I traded it locally and the dealer told me to give him a month and a year and he would check it files. I told him, I cannot be specific.... 96/97/98 and so on. I called an end to it.
about 6 months later, the dealer called me saying he had to go into his files and located my gun sales slip laying on top of the files (meaning he never filed it). Talk about someone was on my side.
Anyway... I made contact with the current owner who agreed to sell me back the gun for a much higher price and when I finally got it in my hands, it was not cared for very well. It was my dream to send it to a high end gunsmith for some cosmetic work and some years later I did.
I chose ACW but ran out of $$$ for a complete finish. It came out nice. I was going to save up some more money and send it back to ACW for checkering and hardened black finish. He closed his shop and runs another shop and does not take in work.
At least I have the piece back and I need to find a smith to finish the job.
These are the only two real regrets that I got back.