I occasionally have to use a car rental service. But from time to time it is very expensive for me. Can you tell me if there is any way to save money on renting a car by using the same company?

It seems to me that if you use only one company to rent a car, there should be some discounts. You just need to talk to them about it. And actually, as an option, you can get acquainted with car rental loyalty programs, which is presented at the link http://drivo.com/loyalty. Everything is described there and you can register right away.