The 2003 Buick Regal is available as a 4-door, 5-seat sedan. Starting at $24,235, the 2003 Buick Regal LS is powered by a 3.8L, 6-cylinder engine mated to anautomatic transmission that returns an EPA estimated 19-mpg in the city and 29-mpg on the highway. The top of the line 2003 Buick Regal GS, priced at $28,235, is powered by a 3.8L, 6-cylinder engine mated to anautomatic transmission that returns an EPA estimated 17-mpg in the city and 27-mpg on the highway.