Terrible state of the car/excess insurance not worth buying

We had booked with Discover 3 months in advance for Bergerac airport as we needed an automatic. The car we booked was a compact but the one they gave us was an MPV - far too big for us. No other choice as nothing else available. The car was in a terrible condition with broken fog and reversing light and a big scrape on the wheel arch (took photos) and alloys gouged and scratched. We also took out Discover excess insurance but when we damaged a wheel/tyre we found that it wasn't covered - it seems only traffic accidents are covered (will buy this separately next time). Nightmare journey back to Bergerac as had to stay in hotel in Limoges and get the train back. Discovered that the excess of 250euros taken at time of booking wasn't the total excess as their website describes "excess" as "deposit" which is very confusing and (I now know) if you want to know the exact amount you have to call them. Would never use this company ever again. We had read Ts & Cs but lesson to us is to "understand" what is meant by the different terminology on the website due, I guess, to the difference in language. Worst experience we have ever had after travelling to many countries and hiring many cars over the years with no problems.