Given a vehicle that did not meet my needs

I have been using Europcar consistently for a number of years but I must be honest my latest experience with them means I will definitely not deal with them again. I phoned to book a vehicle for collection at Wonderboom airport because I needed to make sure that I get a vehicle that can accommodate 5 persons - 3 adults and 2 children. This requirement was made very clear to the lady I spoke to. I was then asked whether a Toyota Corolla would be fine and as I rented a smaller Toyota the previous week which could easily seat 5 I said that this would be fine. However when I arrived at Wonderboom I was presented with a VW Polo Vivo, which must have the smallest cabin for a four door car on the market. It did not have a headrest for a fifth passenger and it also only had a lap belt for the fifth passenger and not a proper full seatbelt, making it clear that the manufacturer did not intend for this vehicle to carry five passenger unless in an absolute emergency. When I enquired about this I was told that the Polo is in the same class as the Toyota and that is it. There was little interest shown in my predicament leaving me to drive more than 300km's with a vehicle not suitable and not safe for my needs. By the way the cars fuel gauge seem to be broken as after having driven 300km's the fuel gauge still read full! I phoned the number on the key for emergencies to check on this but despite numerous attemps the phone would disconnect after only one ring. The car had almost 40 000km's on the clock and the drivers sun visor was absolutely filthy dirty making we wonder if this car had not been retired or retained as a pool car and only given to me because nothing else was available! The booking reference was ********** 62