If their company policy says that you'll get amount X in case of no show that's what you get. You agreed to that term by renting from them.

I'd file a formal complaint to HQ with time,date and the people you have already spoken with and what they said. It will take time and I honestly think that in best case you'll get a coupon for you next rental.

Is it a strong enough case for a small claims court? I can't tell.

But I understand where you coming from and this kinds stuff is just frustrating and make me angry as well.

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Jorge