Join Date: Apr 2006
Location: Los Angeles, California
Programs: United LT-GS, AA LT-Plat, Hyatt LT-Globalist, Hilton LT-Diamond, Marriott LT-Titanium, Hertz PC
Posts: 15,668
I do it all the time. I had three cars rented simultaneously last week: one parked at LAX, one at SFO and one at SEA. It has never been a problem. (I always bring them back). The only thing of which I have to be careful is (i) remember which key belongs to which car and (ii) where the cars are parked.