How to account for discount in marketplace model?
SOME CONTEXT  Say there is a platform/marketplace having multiple sellers and customers. For each transaction happening on this platform between a seller and a customer, the platform gives discount worth 10% of order value to the customer from its own pocket. For eg,  If a customer "C" buys from a seller "S" a product worth $100. For this transaction, the platform gives the customer "C" a discount worth 10% of $100 i.e., $10. The sequence of transaction is as follows:  Transaction #1 -> customer "C" pays seller "S" $90 ($100 - $10 as discount) Transaction #2 -> platform pays seller "S" $10 (such that seller effectively earns $100)  The platform does not earn any revenue from this transaction. Furthermore, it bears $10 loss (10% of order value of $100) from its own pocket. The gross profit for this transaction is -$10. QUESTIONS