Here's one for the record books. A Mustang went under the hammer at Mecum's annual auction in Kissimmee, Florida, on Sunday and sold for $2.2 million, which makes it the most expensive Mustang in the world. That in itself is impressive but we'll remind you that the car was last sold in 2013 for $1.3 million, meaning it's been appreciating at almost $200,000...
