Unacceptable Service

I am extremely disappointed in Budget Rent a Car. My Dad and I booked a Hyundai H1 more than a week ago online and paid upfront for the car. This morning, we get a call to state that they can't get a Hyundai H1 but will give us a IX35. We said no as we have a number of passengers traveling with us and that is why we booked the H1. When we get to the office at Kathu, the car had not even arrived and we were informed that it was still another hour away and would need another 30 minutes to clean and refuel the car. We had booked the car for 16h40 and only received it at 18h20. This has set us back on all our travel plans and to top it all, the VW Kombi allocated to us was filthy inside which we made the agent aware of and endorsed on the rental agreement. The car is not comfortable and we are really unhappy with the replacement car! We booked well in advance to secure the H1, and Budget rent a car did not deliver despite having had our money for over a week. I know that you will argue a similar car, but the least we expect is that when it is booked well in advance that adequate arrangements are made to keep your customer happy! What are you going to do to remedy the problem?