The 2014 Aston Martin DB9 is available as a 2-door, 4-seat coupe. Starting at $183,700, the 2014 Aston Martin DB9 Coupe is powered by a 6.0L , 12 -cylinder engine mated to an automatic transmission that returns an EPA estimated 13-mpg in the city and 19-mpg on the highway. The top of the line 2014Aston MartinDB9Convertible , priced at $ 198,700 , is powered by a 6.0L , 12 - cylinder engine mated to an automatic transmission that returns an EPA estimated 13-mpg in the city and 19-mpg on the highway.