Sell cost as a percentage of buy (excluding discount)

Hi All,

We have a requirement where sell cost is being charged as some percentage of buy allocated cost.Buy cost is being fetched from FedEx​ rating engine (via Kewill) and Kewill returns this cost after applying a discount on it.The part where we are facing problem is that sell cost should be some percentage of buy after excluding discount from buy cost.For example :

Buy Cost without discount = 100 USD
Discount = 10 USD
Final buy Cost (Total Actual Cost) = 100-10 = 90 USD
Desired Sell Cost = 150 % of 100 USD

Please let us know if there is any out of box functionality in OTM or Kewill which can help in mapping this scenario.

Thanks
Shashank