So if everything goes well, everything goes well. But if it doesn't ...

Are there any rental car companies with actually decent customer service? Hertz has been horrible, not giving me my reserved car class and trying to downgrade me without compensation (typically they would upgrade you. Had PC, if that means anything). National is fine cause you don't have to speak to anybody to pick up a car, so you don't get the upsell some other agencies. Even Payless and Fox have been good at times though.
But when you forgot something in the car, often you cannot even get a number to the branch easily, and then find it hard to speak to a human, and then you have to be transferred to lost and found, which may or may not be open?

I don't know if it is better if you have issues with your car and somebody will take care of it right away (luckily haven't had any big issues, when I did just did an exchange)?

Are any of the smaller agencies known for their customer service? I know the big ones don't care, cause you have no choice. But like Silvercar? Or mom and pop shops just in one locale?