They charged me extra for insurance. I paid triple than what I planned
Cons: Their credit card machine was not able to block about 1K Euros from my credit card (for 30 days), which was the condition for not paying for extra insurance. Apparently even a scratch would cost me 600Euros, but I did not mind.
Thus, I was forced to pay triple the quoted price to get the car because of the insurance cost.
The issue was certainly with their card system and could be something they do on purpose to pocket the insurance money. I am confident that my card had no issues because I called my credit card company and they could not see any transaction going through and the money amount was not an issue.