I exchanged a Ford Taurus to the ORD location due to suspected air/faulty fuel line (the fuel gauge was doing whacky things, even for a digital gauge). The managers even approved my returning with a non-full tank due to the fact they'd likely have to drain the gas or at least the fuel line to remedy it. About 45 minutes after leaving the location (which was three, yes three hours after originally arriving, to which the car I was exchanging had sat the entire time exactly where I had parked it) I realized I'd left some items in the car. Returned to ORD location and Budget had already rented the car back out . The lot manager was NONE too happy about them having done so and made clear she had not authorized them to do so. Also turned out the guy they rented it to did not have a phone number on file, AND did not return the car on time (I was in the area through his original return date), so needless to say I never saw those items again. So, at least in my experience, with Avis, if you forget something, consider it gone.