The 2007 Buick LaCrosse is available as a 4-door, 5-seat sedan. Starting at $22,415, the 2007 Buick LaCrosse CX is powered by a 3.8L, 6-cylinder engine mated to an automatic transmission that returns an EPA estimated 20-mpg in the city and 30-mpg on the highway. The top of the line 2007 Buick LaCrosse CXS, priced at $27,040, is powered by a 3.6L, 6-cylinder engine mated to an automatic transmission that returns an EPA estimated 19-mpg in the city and 27-mpg on the highway.