Pathetic cars and service rip people of they money

I rented a vehicle with them on the 5th of December the vehicles are old and seems not to have been services.i paid deposit and rental In a week time as I drove the car it stopped in the middle of the road they got a mechanic found out it was the engin they exchanged for another vehicle this vehicle hooter was not working, the water for the wipers was not coming out as that was also not working the tyres wer worn out had to call them again for another vehicle .I ended up taking the car back on the 9th of December today only they pay my deposit refund back without any invoice nothing and guess what no explantion they pay me back only r1100 from my r3900 the only deduction was suppose to be r500 as I was quoted by the sales lady as I asked them to pick the vehicle up I've been emailing and calling them they not responding