HERTZ IS A ****MER!!

I rented a car from Hertz at the airport. I wanted to extend the car for 3 days. I called them and I spoke to one of their consultants, who then said for an extra 3 days the price will be R845.00. I agreed and the money was debited from my account. When I returned the car, the company deducts R1423.00 from account again. When I called to enquire, I was told that the second charge is for the extra 3 days. The correct price was the second price not the first one. They did reverse the R845.00. However, that's not the price agreed to. I extended the rental under the impression it's R845 not R1423.00. The person who made a mistake should pay the difference not me. I believe they deliberately gave me a lesser price but charged me more so I can extend the rental. This is daylight ******* and when I contact them via emails they aren't responding to my emails. So, I'm warning people to be very careful when they are renting from this company because they will **** you of your hard earned money and not even bother to help you. This is absolutely disgusting and unacceptable. BEWARE OF ****MERS