rotten service

I booked and paid for vehicle through rentalcars.com, the deal stated im getting 1****ms for the duration I hired the car (that was paid for), I took a Toyota yaris from the cape town airport on the 17th December and drove down to Port Elizabeth with my family, while driving to my destination I noticed every time when I start the keyless car doesn't start immediately but didn't know it was faulty at the time, I managed to arrive in PE, the morning we had to attend a function the car wouldn't start at all, I tried starting the car for almost 30 minutes but still didn't start, I started to panic because we were now running late because of this car, I had to make someone to take my family to the function while I had to drive all the way to the nearest avis at the airport which is 45 minutes away to exchange the car, got there told my story and they gave me a polo vivo with scratches on it (another downer), had to drive back another 45 minutes to the venue. Drove back to cape town the next morning, handed the vehicle over, now im being told stories about my money and being over-charged. This is my concern; Why would my km be reduced if I booked and paid for those kms already, that makes no sense to me as I should be getting everything I paid for. Also what about the kms I travelled to and from that Port Elizabeth airport to have the car replaced, clearly that was not my fault. what about my time, money, fuel, energy and inconvenience. Your car was faulty, how it that my problem if you provide your customers with faulty vehicles to rent. I will never use this company again!