SIXT is a sleazy outfit

SIXT is the most sleazy outfit. They never have the class of car that you reserve. They try to sell you an upgrade or offer a vehicle that is inferior to the class that was booked. This happened to us twice, once in Germany and once in France. I will never again rent from SIXT. To add insult to injury, they overcharged me. I rented for 4 days in Nice, France but returned a day earlier. The rep at the counter told me that one day's credit would be automatically posted after 48 hours. It is now 12 days and the company is making excuses for not giving the credit. I am raising a dispute with credit card company. Go with National or Hertz. They are the best in the business. Nat Natarajan