Min Profit Margin = margin above landed_cost + fba fees + referral fees + TACOS

Example: You know that the min selling price for the ASIN should be at $30:

To calculate: $30 (Price) - $7 (landed_cost) - 4.5 (fba fees) - 3 (referral fees) = $15.5 (gross margin)

Margin on Cost: $15.5/$30 = 51.6%

Min Net Profit Margin (w/Ads) = 51.6% - 20% (TACOS) = 31.6%