Specifies the different costs that the modified bill can be
based on.
Values:
REBILLING_BASIS_UNSPECIFIED (0):
Not used.
COST_AT_LIST (1):
Use the list cost, also known as the MSRP.
DIRECT_CUSTOMER_COST (2):
Pass through all discounts except the
Reseller Program Discount. If this is the
default cost base and no adjustments are
specified, the output cost will be exactly what
the customer would see if they viewed the bill
in the Google Cloud Console.
