You know what really grinds my gears?!

[Ken]

*Work phone rings*

Me "Thank you for calling...how can I help you?"
Customer "Well we had an estimated lease for 12 months for this equipment and returned it at month 9 but were charged for a full year. What gives?"
Me "Well that is how our contracts work which is reflected by our terms and conditions. You agree to pay the full lease amount no matter when you return it. In return we provide pricing incentives for longer term deals."
Customer "Well because of this I will never do business with you again!"
Me "I'm sorry to hear that. This is standard practice throughout the industry so please be aware of that for future rentals with any company."
Customer "No it isn't. X company does not do this!"
Me "Goodbye and please never call me again"

Not my problem you didn't read the TWO page agreement. Also not a difficult concept to understand. If you rent something for 1 month the rate is extremely inflated. If you rent it for 12 the rate is drastically lower incentivizing you to rent it for longer.

Expected Customer to switch to, "Former Customer" halfway through haha.

But yeah, hate that crap. Not my fault that you didn't read the T&C's before making a purchase. If you had any issues with it you probably should have raised them before making the purchase.