The 2017 BMW ALPINA B6 Gran Coupe is available as a 4-door, 5-seat sedan. Starting at $122,500, the 2017 BMW ALPINA B6 Gran Coupe Base is powered by a 4.4L, 8-cylinder engine mated to an automatic transmission that returns an EPA estimated 15-mpg in the city and 24-mpg on the highway.