Let's see...free = $0.00
Cost to you = $0.00
Hummm...seems pretty inexpensive to me.
Seriously, I have Avis Preferred Select, Hertz #1 Gold, and Nat'l Emerald. I use Avis for the majority of my rentals, and since Nat'l EA has gone to pot, Hertz is my #2 choice. I don't like Fords, but the service I typically get at Hertz with the #1 Club is worth the cost of your time to fill out the membership app.
Who knows, you might like them enough to rent alot and get 5* or whatever the level above that is and get some cool cars.
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Not sure where I'm going, but I'm getting there fast.