trying to create an expression to determine how to price a product for an online channel based on their 12% referral fee. the product price would need to consists of my price plus the referral fee. the trouble is that i cannot predict what the fee will be since it is based upon my final selling price. i'm thinking there needs to be a 2 level equation. the first one to calculate the estimated referral fee and the second one to add that value to my selling price?