The phrase that comes to mind is "contract of adhesion". U-Haul says they will reimburse you $50 for a no-show. You had no opportunity to negotiate that term, it was "take it or leave it". Yet your actual damages are well in excess of $50. A lot of judges' ears will perk up when they hear the above phrase. A lot of people have been surprised to find that their iron clad contracts are worth nothing if they haven't dealt fairly.

Small claims court costs very little. You risk half a day of your time. I'd say try it.

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Not in jail.