You know what sucks about buying ads? Paying for the privilege of being able to buy said ads. So no, there are no fees to use me.
Let's be real. 4 am isn't worth as much to you as peak hour. Tell your campaign to up your bid for the times you actually want.
Seriously, the only thing you pay for is what you're actually buying. Why wouldn't you sign up for that?
No...Really, why are you still reading this?