I am on your side except
Bonanza36
I agree with you almost entirely the part I have a problem with is " The cancelled reservation took place on March 19, 2013. My travel did not occur until the first week of May. I had forgotten about it. How would any reasonable person think to double check a counter agent error almost two months later?"
Your job is to check the contract you are signing.
The fact you may be in a hurry or other excuses does not wash with me. You are trusting a low level commission hungry employee to do everything right and in your favor. Think about how much grief and time not taking a minute to check the contract has cost you. I check the contract every time. I Take pictures of the car every time. I get gas receipts every time. Those are the issues always cropping up so I try to prevent them. EVERYONE SHOULD READ THE CONTRACT before leaving