The 2012 Scion xB is available as a 4-door, 5-seat wagon. Starting at $16,300, the 2012 Scion xB Base (M5) is powered by a 2.4L , 4 -cylinder engine mated to a manual transmission that returns an EPA estimated 22-mpg in the city and 28-mpg on the highway. The top of the line 2012ScionxBRelease Series 9.0 (A4) , priced at $ 19,060 , is powered by a 2.4L , 4 - cylinder engine mated to an automatic transmission that returns an EPA estimated 22-mpg in the city and 28-mpg on the highway.