The 2012 Mercedes-Benz R-Class is available as a 4-door, 5-seat sport utility. Starting at $52,690, the 2012 Mercedes-Benz R-Class R 350 is powered by a 3.5L , 6 -cylinder engine mated to an automatic transmission that returns an EPA estimated 16-mpg in the city and 21-mpg on the highway. The top of the line 2012Mercedes-BenzR-ClassR 350 BlueTEC , priced at $ 53,840 , is powered by a 3.0L , 6 - cylinder engine mated to an automatic transmission that returns an EPA estimated 18-mpg in the city and 23-mpg on the highway.