The car was rented using a German Lufthansa VISA card, but I assume that there are similar laws as in the US.
I never heard back from the rental company after they recovered the car, I never went back into their office, which was in a different city many hundred miles away after all. When I phoned them to notify them of the breakdown they mentioned that I may have been in breach of contract but nothing else.
The reason for disputing the charge was initially that I did not know the company that charged me (never signed anything to them).
From VISA, I then received a letter today stating that they have receipts and because I agreed to pay for all costs in the agreement there is nothing they can do and I have to take it up with the car rental company directly. VISA sent a copy of the letter that the car rental company apparently sent to me (but I assume which was only drawn up once they got a letter from VISA) detailing the charges (but only one tax invoice was part of their receipts, another one was a quote for repair, and other parts of their claims were not substantiated). The letter also stated that a refund has been authorized for the difference between the actual cost and what they took from my credit card. This refund hasn't appeared on my card either.
SmilingBoy.