Seemingly good company let down by an old, broken car fleet

We decided to hire a car for 7 days from Autoreisen (Tenerife south airport) based on the generally good reviews for their service. Unfortunately, the vehicle we had (an older Citroen C3) was absolutely the worst hire car I ever had for nearly 2 decades of travelling. Not only was the car full of scratches and dents with mismatching hubcaps, its interior was also dirty with many broken trims. The car squeaked alarmingly when driven over bumps and its indicator showed that it should have been serviced about 4000 km ago. Finally, we found out (too late) that the fuel gauge was also defective. On our way back to the airport to return the car, the gauge would not response to multiple top-offs at petrol stations until it suddenly jumped to full after we spent an extra €30 in fuel (we only needed to top-off to half). When we complained it to the return office clerk, she was not surprise at all as it appeared to be a common problem with the car. Sadly, I don't think our car was an isolated case as I could easily identify Autoreisen Citroen C3s in Tenerife by their mis-matching hubcaps! Although the staffs at Autoreisen offices are generally courteous, ultimately they cannot do anything to reimburse us and their on-line reservation service offered no help. Try them at your own risk but if you do, make sure you insist on a newer vehicle, if they have any.