Car Hire Rip Off

It was a disaster.
It started off well, I selected a car we needed big enough for 5 people and luggage - notionally a Renault Scenic or similar. We pre-paid this from the UK expecting that we would arrive, get the keys and off we would go.

When we arrived it was the usual excuse that that car wasn't available but I could have a similar one - first we were offered a BMW 1 series - a compact car that could not fit in even 2 suitcases, so we were then offered an Audi A3 (same issue). I was told we would have to upgrade to get a bigger car - I saw some bigger cars there and asked for one of those, but was told they were reserved for customers - I asked why my car wasn't reserved for me - no answer. We then tried an A4 (all the while messing about carrying our luggage from car to car and then going back to the office to try again) whose boot was still too small and eventually got a Ford CMax which was just about OK.

The situation was compounded by the fact our car was broken into on the last night of our holiday by smashing the front quarter light and gaining access somehow, without the alarm going off. We had a suitcase stolen from the boot, which was not visible from the outside as it was in the boot under the parcel shelf. On dropping off the car we were charged €300+ for the new window (seems very expensive) and were given a receipt with that amount circled, but were actually charged an additional €250+ for VAT on the rental, but this was almost hidden away on the receipt so it was not obvious it was being charged and was never explained. WE had taken out a policy to reduce our excess to 0 so am expecting this to be refunded and have opened a ticket with Atlas to get the upgrade money refunded, the additional VAT refunded and also to get information on how to claim back the excess we were forced to pay. I am also awaiting for advice on how to claim on the insurance for our missing suitcase and its contents.

As you can imagine this is not what I expected and I think the service has been terrible, having spoken to some other friends who also rented cars and who also were hit with unexplained hidden charges, I am of a mind to think this is the industry norm, whenever you go to a desk they try and sell you more insurance whatever you have purchased and then the charges mount up, it is not explained at all. What is the point of pre-paying and then still being hit with additional charges? I would NOT recommend Atlas nor Budget to anyone.