From Granada to Seville to Madrid, Spain

Europcar was very bad. I booked a manual car on Zuzuche.com, but at the location, the staff recommended an automatic car with an additional 10 euros per day. Considering the narrow roads in Europe, I accepted the upgrade. Since it was an upgrade, I only confirmed the upgrade fee and didn't look through the contract thoroughly. Who would have known that when returning the car, the upgrade fee turned out to be 20 euros per day. Without my consent, they had also added glass insurance and associated taxes, making the final bill double the original cost. When we realized the problem, we contacted the return location, who communicated with the rental location. Since the relevant staff wasn't working that day, we agreed to resolve it the next morning. We called at 9 AM, but were told the staff hadn't arrived and asked if they should call us back. Trusting them, we waited for their call, but they never contacted us. When we tried calling back multiple times, no one answered, and it kept going to fax. We never had a chance to verify the situation with the responsible staff member. Later, we checked reviews from UK and US customers and found similar complaints, indicating a widespread issue with honesty and integrity at this company. Out of the four car rentals I booked on Zuzuche.com, three were in the US and were excellent, but the experience in Spain was very disappointing.