I booked a vehicle online from CarRentals.com to pick it up in Munich Airport on July 5, 2018. I went through the simple booking process, and secured the booking by the Chase Ink Business card to use a Travel Benefit from my Chase Ink business credit card for the collision insurance coverage. It was no mentioning or warnings that Chase Card insurance coverage will not be accepted by CarRentals.com. No specific insurance requirements have been mentioned. At the time of the booking the amount due was quoted as $368, and that was the reason I choose this agency. When I came to pick up my rental car to Munich, the agent did not want to accept Chase Card insurance coverage, referring to the fine print in the company's Terms and Conditions, forcing me to purchase the additional insurance according to the CarRentals.com regulations and requirements. As a result, my amount due jumped to $814 which is 122% higher than original quote. The agent hasn't been giving me a choice: either purchase the insurance that I didn't need, or no car would be released to me. This was a classical rip-off case when the business traps its customer, not mentioning any additional pending charges at the time of booking, not providing any quotes for it, and leaving no choice when you came to pick up the car in the beginning of your trip. I tried to call the Customer Service of CarRentals.com, but there was no help from there. I understand that the CarRentals.com is a third-party agency and is a subject to the certain rules and regulations. But it also has obligations to clearly inform the customers beforehand in what kind an agreement they are engaging. The business model of CarRentals.com as well as its web site is designed to mislead customers by quoting them the reasonably low rental prices and hiding the biggest part of the pending expense behind the fine print of the Terms and Conditions. The practice of declining the Collision Waver benefits from the Chase Business credit card by CarRentals.com is quite unusual for any car rental company in US. I never heard about it renting cars for the last 30+ years in US and abroad. The request to the customer to provide the written proof issued by the credit card's insurance company prior the renting is even more strange. Never-the-less, CarRental.com, as a business, has rights to implement these requirements. BUT IT SHOULD MAKE ITS CUSTOMERS AWARE about these unusual requirements. From the moment the credit card is being submitted to secure the booking customer should be aware the he/she will be liable for the substantial additional insurance cost. The quote of this insurance HAS TO BE GIVEN PRIOR THE CHECKING OUT, it has to be stated in bold letters over the quotation given, not when the unsuspecting customer comes to pick up the car. Especially when the cost of the insurance exceeds the rent quotation by 122%. None of this information has been given or explained to me: no insurance requirements, no quotation. CarRentals.com should provide its customers with information, not to hide it, setting people up in a state of the shocking surprise when it is time to pick up the car, and too late to shop around for another rental agency. The warnings should be given on each step of the booking. Without these warnings this business model is a mousetrap which has no right to run under the jurisdiction of the Department of Consumer Affairs.