Rental car savings

While researching rental cars i discovered there was a 20% surcharge on rentals originating from the airport. Since were renting for almost three weeks 20% is a lot of money. I found a Hertz rental office a few S-bahn (regional train) stops from the airport. And when i called and spoke to a different hertz representative to change the reservation they gave me a better rate of less than 19eur per day for the same midsize car.

Only downside is that the remote Hertz location didn't have the car class we reserved so we have to wait about an hour for a car to be delivered. They did upgrade us to a wagon and to a diesel. Diesel fuel is 30 cents a liter cheaper gets better mpg and we are saving 500eur from the original reservations.