This goes back about five years. I was driving north on I-95 in my six month old BMW Z5 3.0. I was in the left lane and a flatbed truck hauling crushed autos was in the center lane a short distance ahead. A piece of sheet metal came flying off one of the cars and it looked like a piece of paper fluttering in the wind.
Not knowing which way it was going to go, I held my line and hit my brakes. At the last possible moment as I slowed through fifty MPH or so, I hooked a left onto the center divider with the left tires but it wasn't enough. The piece of scrap metal just nicked my right rear fender above the wheel well. One more foot to the left and......well, it doesn't matter now.
Most of the scuff marks came off with rubbing compound. I brought it to BMW for a touch up and with a florescent light they showed me the small dent.
Well at least the truck pulled over and gave me his phone number. They took care of the repair bill. I told the shop just to match the paint and touch up the small area. Instead they painted the entire fender.
When I traded the car in, the adjuster saw the fender had been repainted and knocked $500 off the trade in value. The way he could tell was by looking in water channel with the trunk open. He showed me the glossy finish in there compared to the mat finish on the other side.
Eric