The 2018 Audi A5 is available as a 4-door, 5-seat hatchback. Starting at $42,800, the 2018 Audi A5 (S tronic) quattro Coupe is powered by a 2.0L , 4 -cylinder engine mated to an automatic transmission that returns an EPA estimated 24-mpg in the city and 34-mpg on the highway. The top of the line 2018AudiA5quattro Sportback , priced at $ 42,600 , is powered by a 2.0L , 4 - cylinder engine mated to an automatic transmission that returns an EPA estimated 24-mpg in the city and 34-mpg on the highway.