Generate formula to calculate sell price with respect to buy price, buy& sell out fees and desired profit margin percentage (changing variable)

[Briefshallot8004]

Hi I’m currently doing trading and I want to generate a formula that will help me determine what the sell price should be to achieve a desired profit margin percentage with respect to the following variables:

Cost price: (changing variable)
Buy fee: 0.1% (fixed variable)
Sell fee: 0.1% (fixed variable)
profit margin percentage (changing variable - 1%, 2%, 3% etc)
Sell price: (desired figure)

 

[Cubist]

Buy fee: 0.1% (fixed variable)
Sell fee: 0.1% (fixed variable)

How should these percentages be applied? Compounded or directly to the cost price?
e.g. for an item with a buy cost of $100, should it be 100(1+0.001)(1+0.001) or 100(1+0.001) + 100(1+0.001)?