Who has told a buyer that what you have is not what they need?

About 10 to 12 years ago, I put a nice 71 Duster with a 451 stroker & 3 stages of nitrous on it up for sale. The car was well known in my area as being a quick car & the one to beat. A high school grad came by & just had to have it, so I took him for ride out the back side of the area we lived in at the time. I ran him down the street with two stages lit & he was hooked. He said he would be back the next day with the money & I got to thinking, he'll kill himself in this car. I took it to the shop & striped off the 2 big stages of nitrous & left the last 25 hp shot on it. He came the next day with cash in hand & I tried to talk him out of it. He wouldn't have it, so I sold the car to him. Two weeks later, I get a phone call from him wanting to know if I want to buy the car back. I go take a look & the car is shaped like a banana where he wrapped it around a tree. I bought the car back for 300 bucks & the drive train is in storage still while I look for another candidate for it, I scrapped all of the damage sheet metal, the body was toast but I was able to salvage the deck lid & hood.