The 2011 Aston Martin DB9 is available as a 2-door, 4-seat coupe. Starting at $187,615, the 2011 Aston Martin DB9 Coupe is powered by a 6.0L , 12 -cylinder engine mated to a manual transmission that returns an EPA estimated 11-mpg in the city and 17-mpg on the highway. The top of the line 2011Aston MartinDB9Convertible , priced at $ 201,115 , is powered by a 6.0L , 12 - cylinder engine mated to a manual transmission that returns an EPA estimated 11-mpg in the city and 17-mpg on the highway.