The 2018 Infiniti Q50 Hybrid is available as a 4-door, 5-seat sedan. Starting at $50,600, the 2018 Infiniti Q50 Hybrid RWD is powered by a 3.5L , 6 -cylinder engine mated to an automatic transmission that returns an EPA estimated 27-mpg in the city and 32-mpg on the highway. The top of the line 2018InfinitiQ50 HybridAWD , priced at $ 52,600 , is powered by a 3.5L , 6 - cylinder engine mated to an automatic transmission that returns an EPA estimated 26-mpg in the city and 30-mpg on the highway.