Originally Posted by
CMK10
All of that is covered by Damage Waiver. What the OP is asking about is Supplemental Liability Protection which covers damage to other vehicles/property. However, as each state gives you a minimum of $10-30,000 in Liability Protection, you'd have to "hit a fuel truck or a Ferrari to need it" as I used to say when I worked there.
My father once hit a Lotus with his rental car! The odds of hitting a ferrari or fuel truck are not as slim as one would think!