This highly collectible one-off Bentley Continental GT styled by Zagato is now up for sale on eBay.Back in 2008, Bentley partnered up with the legendary Milan, Italy based design house Zagato to build a very special version of the Continental GT. The result was the Continental GTZ and it was officially unveiled at the 2008 Geneva Motor Show. The original plan was to build nine units. But in order to have one, customers first had to buy the $200,000 Continental GT Speed and then pay an additional €550,000 for the Zagato styling. All told, the GTZ cost €800,000 ($1.1 million).So what did that extra €550k buy exactly? Pure Italian goodness. To start with, it features Zagato's signature double-bubble roof, a round tail with a unique taillight design, and even a hand-painted pin-stripe that's the same color as the tan interior.The leather trim was also re-upholstered in even higher quality leather complete with Z motifs that have been stitched into the seatbacks. Want more? There's also full leather headlining for the roof and keyless ignition. It's powered by the same twin turbo 6.0-liter 600hp W12 as the regular version and is mated to a six-speed automatic.