The 2010 Lexus RX 450h is available as a 4-door, 5-seat sport utility. Starting at $42,685, the 2010 Lexus RX 450h FWD is powered by a 3.5L , 6 -cylinder engine mated to an automatic transmission that returns an EPA estimated 32-mpg in the city and 28-mpg on the highway. The top of the line 2010LexusRX 450hAWD , priced at $ 44,275 , is powered by a 3.5L , 6 - cylinder engine mated to an automatic transmission that returns an EPA estimated 30-mpg in the city and 28-mpg on the highway.