This argument is not required if the Seller Service charging the token has a priceModel of PAY_PER_USE
When not provided, Skyfire will automatically charge the price of the Seller Service that is charging the token
When provided, the chargeAmount must be
Greater than 0
Less than or equal to the tokenAmount.
Less than or equal to the balance on the token if you have charged a partial amount to this token already.
The balance will be less than or equal to the tokenAmount.
We will be adding a token introspection API that you can use to determine the balance on a token if you are unable to keep track of your partial amount charges.
We have selected string representation as a way to preserve precision in numbers.
