Originally Posted by sdsearch

Talk about something that's not specifiable in advance! All you can select in advance is the car category, for which they're giving an example. You cannot select a specific exact car model in advance online, not at Avis and (last I checked) not at Hertz either.

How likely you are to get a specific car may or may not be guessable if you have knowledge of what that location tends to stock in a particular category (which only a frequent renter at that specific location would tend to know).