Rate Plans enable you to create pricing structures that vary by the number of items purchased. You can also define pricing Tiers, which specify one price for the first number of a given Product, and a different price for subsequent blocks of the same Product. You can define an included number of items, at no additional charge, and set minimum and maximum Billing Cycle charge limits, if you like.
For example, a Rate Plan might be designed such that each Billing Cycle provides access to 50 GB of storage at $12 per month, with the first 100 GB after the initial 50 billed at $.20/GB per month, the next 100 billed at $.15/GB per month and anything over 200 GB bllled at $.10/GB per month.
With Rate Plans, Product pricing varies by the number of items used; whereas with standard Product pricing, the price for units of the Product remains the same regardless of the quantity used.