The 2021 Infiniti Q50 is available as a 4-door, 5-seat sedan. Starting at $36,700, the 2021 Infiniti Q50 PURE RWD is powered by a 3.0LL , 6 -cylinder engine mated to an automatic transmission that returns an EPA estimated 20-mpg in the city and 29-mpg on the highway. The top of the line 2021InfinitiQ50SIGNATURE EDITION AWD , priced at $ 50,200 , is powered by a 3.0LL , 6 - cylinder engine mated to an automatic transmission that returns an EPA estimated 19-mpg in the city and 27-mpg on the highway.