Hertz - Volvo XC90 at SFO

they used to keep some XC90 at SFO, but it can no longer be found anymore on the internet booking.

also, i notice some new XC70 parked inside the garage last time when i was returning the car, but i have never seen it on the internet either.

are these cars still around? how am i able to book it? or what class does it belong to?

thanks