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Isn't it obvious that price drops with quantity?

A reservation is a pledge that the customer will purchase the item later. The reservation costs $1-3 depending on where the buyer is, and is paid through a cell phone. By having it be paid, it is simply more reliable. No one wastes money, and these are dissolving costs in the total discount.

I believe this is the minimal information. The unit price, the current and the maximum quantity price. What do you think is excess?

Thanks for the comment.