The 2006 Buick Terraza is available as a 4-door, 7-seat passenger van. Starting at $27,250, the 2006 Buick Terraza CX FWD is powered by a 3.5L , 6 -cylinder engine mated to an automatic transmission that returns an EPA estimated 18-mpg in the city and 25-mpg on the highway. The top of the line 2006BuickTerrazaCXL AWD , priced at $ 33,250 , is powered by a 3.5L , 6 - cylinder engine mated to an automatic transmission that returns an EPA estimated 17-mpg in the city and 23-mpg on the highway.