Please remember that if you use a taxi between Athens Airport and hotels / areas in inner city ring in Athens, fare is flat ( 35 euros at daytime, 50 euros at night time ), with ALL applicable surcharges included.
So, toll cost, luggage fee, VAT, airport charge, meter start are ALL included. Don't fall for some taxi driver that may tell you "it's 35 euros + toll cost etc ).
More info here:
Only thing not included is appointments, meaning calling a radio call taxi through your hotel reception or making an appointment to have a taxi waiting for you to take you from point a to point b. Nevertheless ALL applicable charges on a normal taxi ride are included.