Approaching the close of the last century, I owned a twin with a good friend. After flying it for some time, a costly AD plus the fact the engines were we’ll past TBO meant it was time to send them out for overhaul. We sent them to a shop I thought was a good one and paid in advance for a one-month turnaround. We got them back six months later. They were junk. The FAA got involved and I found out the FAA has a criminal division. The owner of the overhaul shop spent a year in the federal slam for forging logbook entries on our, and other, engines.
We sent the engines out, again, to Blueprint Engines (sadly, since defunct) and G & N Aircraft (still alive and we’ll in Griffith, Indiana). We were smart enough by then to only pay half up front. They came back on time and ran happily throughout our ownership of the airplane.