Reserved an "intermediate" (Dodge Stratus or similar) at MHT several months ago and when I got there they gave me the keys to a Jeep Wrangler. Kind of palmed it over to me so I would be less likely to look at the tag. I walked out to the lot and saw the vehicle before I realized what they'd done.

Couldn't take the Jeep because I would be squiring my elderly mom around. Hiked back to the counter and they reluctantly gave me an Intrepid at no extra charge... but there's no way they could argue that a Wrangler is an intermediate car.

Bottom line: Dollar franchisees are under local pressure to rent out their own, owned cars first (and a motley collection they may be) before dipping into cars from the one-way pool that might also be available.

Always argue, because when they try to give you a car you didn't reserve they're serving their agenda, not yours.