What’s the worst amount of body damage/bondo you discovered after you bought the car??

I finally found a 72 Duster in 2001 that was rust (a roller) free except for pinholes in the floorboard. I was excited about the price and subsequently didn’t note ce that the body lines on the rear quarter were non existent. I took it home and started grinding it down to bare metal starting at the front and working my way back. The complete quarters were filled with bondo AND they had stuffed newspapers in to fill the holes before putting the bondo!!
I didn’t tell anyone about it for a while as I was completely embarrassed about it but now me and my car buddies laugh about it all the time. I’d like to hear some of your stories about what happened to you. Don’t be embarrassed anyone who says they haven’t made a mistake is a damn liar. Doesn’t have to be about the body. For example when i built my first slant 6 i buttoned it up and turned the crank to see how many ft lbs it took to turn a complete revolution- halfway thru it locked. I had left a can of permeated gasket sealer in there. So I fixed that and get it running and took it out for a test drive and the oil pressure was great from for 5 minutes and it slowly sunk down to nothing and I returned to the shop with a bearing knock. I had not bothered to check what the Maltese cross on the number pad meant. The crank was 10thousandths under from the factory. LMAO