The 2012 BMW M3 is available as a 2-door, 4-seat coupe. Starting at $60,100, the 2012 BMW M3 Coupe is powered by a 4.0L , 8 -cylinder engine mated to a manual transmission that returns an EPA estimated 14-mpg in the city and 20-mpg on the highway. The top of the line 2012BMWM3Convertible , priced at $ 68,750 , is powered by a 4.0L , 8 - cylinder engine mated to a manual transmission that returns an EPA estimated 13-mpg in the city and 20-mpg on the highway.