The 2015 BMW M4 is available as a 2-door, 4-seat coupe. Starting at $64,200, the 2015 BMW M4 Coupe is powered by a 3.0L , 6 -cylinder engine mated to a manual transmission that returns an EPA estimated 17-mpg in the city and 26-mpg on the highway. The top of the line 2015BMWM4Convertible , priced at $ 72,500 , is powered by a 3.0L , 6 - cylinder engine mated to a manual transmission that returns an EPA estimated 17-mpg in the city and 26-mpg on the highway.