The 2020 MINI Convertible is available as a 2-door, 4-seat convertible. Starting at $28,400, the 2020 MINI Convertible (DCT) is powered by a 1.5LL , 3 -cylinder engine mated to an automatic transmission that returns an EPA estimated 28-mpg in the city and 36-mpg on the highway. The top of the line 2020MINIConvertibleJohn Works (A8) , priced at $ 38,400 , is powered by a 2.0LL , 4 - cylinder engine mated to an automatic transmission that returns an EPA estimated 25-mpg in the city and 33-mpg on the highway.