Having booked car rental through carrentals.com I didn't know exactly what company I would be booked with until I had paid the final amount. I had previously rented a car through this site and they had booked me with a brilliant rental company so I trusted their judgement completely. After my recent experience I will think again.

I can honestly say I've never received such shoddy and unprofessional service from any company before.

I arrived at Belfast International Airport and phoned the company to let them know I had arrived (as directed to do on the rental instructions). My flight arrived in early so I was phoning 15 minutes before my rental was due to be picked up. The person arrived at the office on time but we didn't leave until about 7.30-7.45 due to issues with the pick up which led to us being late for our hotel reservations.

Upon arrival I was told the company would have to take £1200 from my credit card as a holding deposit in case of any damages. My bank doesn't allow large amounts to be withdrawn without pre-authorised permission - which I would have got if I had known in advance I would have had to do this....I then offered to pay it on debit and was told the only way to do this was to pay an extra fee to reduce the excess. I ended up having to pay another £30 (on top of the already extra £32 for being under 25....by a month!) just for the pleasure of using my debit card.

In retrospect the above was a god-send as I didn't know how much of a circus this company was. We were handed the keys for the car and told to sign a form saying we agreed with the condition the car was in...I insisted I wanted to check the car over before signing anything but this was refused (in reflection I should have run a mile!). We were told the car was parked round the side of the building but when we went round it wasn't in the place we were told to look. After going in twice to double check I was looking in the right place I eventually found it (by ignoring the wrong instructions given) and it was parked in what looked like a car dump yard in the middle of 6 other cars with a Mercedes blocking it in and another car blocking the other side. I stated it was impossible to get the car out of the "space" and was told by the sales assistant it was easily accessible. I refused and asked her to move some of the surrounding cars. She moved two of the cars and then told me to reverse our car out. Our car was still jammed tightly against a wall (approx. 10 cm from it) and had a car close in front and at the other side. I raised concern but did as instructed and carefully edged backwards. I stopped as I heard a noise and switched off the engine as I was concerned I might have damaged the car and I asked the assistant to reverse the car as I didn't want to be responsible for damages.

When we had first arrived at the car, my friend and I carefully checked the 3 sides of the car we had access to to check the previous damages were marked correctly (we were unable to access the side closest to the wall as it was parked so closely to the wall. We noticed there was at least one significant missed damaged area. The rear number plate was loose and hanging off at one side. I asked the assistant to mark this on the list and she marked it on my copy but not hers. I explained I wanted her to mark it on her copy too so we weren't accused of causing that when we returned the car. She said she didn't need to do that. I pointed out that in that case my sheet was invalid as I could technically add anything I wanted and it would be best for their company if they signed both of the sheets so people didn't try and scam them.

When we reviewed the final side of the car once it had been fully reversed we noticed a slight scrape on the left wing mirror (the one that had been closest to the wall). The assistant insisted this was new damage and I had caused it. I was concerned as I knew I had heard a sound and could quite easily have caused this but raised concern that the car was parked in a bad place and it was impossible to move it without damaging it. The assistant's tone was accusing, abrupt and defensive.

After much discussion she phoned her manager and said that "there were two customers here who had damaged a and we're refusing to pay for it". She gave wrong information and changed the story to absolve her of responsibility. She told the manager she had offered to reverse the car from the outset of the keys being handed over....this had never happened. When we questioned her on this she was rude, defensive and completely lied to us and her manager.

Right from the outset of our arrival she seemed uninterested, unprofessional and wasn't even in the sixt uniform.

The result is they have taken the full amount for the excess and we will only get some of it returned when the vehicle goes to get "fixed". Financially this is not a problem as I was sensible enough to take a separate insurance policy out with another company before renting the car. However, I wanted to write this review to show my disgust in the lack of good public relations in the company and highlight their lack of professionalism so that in future others don't get scammed in the same way we were.

Result: NEVER rent a car from Sixt.