Product difference /untidy vehicle/poor tyres

I hired a Mercedes 250d 4x4 bakkie at the King Shaka Airport. I booked this vehicle about a month ago on Thrifty website. I needed the vehicle for the week of the 8th-13th March as it is my wife's birthday and I am taking the family to the South Coast. I was looking forward to this top of the range bakkie but I was most disappointed when I went to fetch this vehicle today. The lady at the King Shaka branch was most helpful. She advise me when I arrive and provided my details that the vehicle had a metal canopy and I did not know what this was and she advise me to inspect the vehicle before finalizing the booking. I assumed that the vehicle I booked on the website would be the exact same vehicle at the Thrifty branch. I was shocked and totally disgusted when I viewed the vehicle and the canopy was a metal canopy. An ugly looking thing with no windows. This is not what I had booked for as I needed a normal canopy with windows, like the one on the website. I went back to office and helpful lady tried to arrange another vehicle but there was none available and I was forced to take this vehicle. Further to the above, the vehicle I hired, was not very clean and inside the canopy was completely dirty. Also the vehicle has sensor problem as it keeps giving me a warning light to check the tyre pressure. When I referred this back to guy releasing the vehicle, he stated that this is a common fault but the tyre pressure is fine. Further to the above I noted that the life of three of tyre is less than 50% and the forth is almost flat. I have hired many vehicles from Thrifty and always been most satisfied with their vehicles but this vehicle disappoints me and is not acceptable that I must be forced to accept a vehicle that is not 100% clean with a some issues. I pray to God that the vehicle takes me and my family safely to holiday destination in South Coast and back home.