The 2006 MINI Cooper is available as a 2-door, 4-seat hatchback. Starting at $17,450, the 2006 MINI Cooper Hatchback is powered by a 1.6L , 4 -cylinder engine mated to a manual transmission that returns an EPA estimated 28-mpg in the city and 36-mpg on the highway. The top of the line 2006MINICooperConvertible , priced at $ 21,950 , is powered by a 1.6L , 4 - cylinder engine mated to a manual transmission that returns an EPA estimated 27-mpg in the city and 35-mpg on the highway.