First time (attempted) rental. Plane touches down and I receive a hastily written text informing me that Silvercar doesn't actually have the car I was promised. Their suggested resolution was for me to receive my car halfway into my trip, with no mention of any discount for my trouble, a waiver for all the travel expenses I would incur in the meantime, or the obvious option to just rent a nice car from a local agency so they have one to deliver to me. Hell, if it were my company I'd let the customer borrow my personal car until one was ready for him.
I ended up scrambling to rent a Kia Soul last minute for more money than my Audi would have been. But at least Avis didn't bait-and-switch me. What a two-bit operation and the exact opposite of how they advertise themselves.