How Do You Work Out Your Advance Profit Margins?

When it comes to porn sites?

Typically with physical products, you know what your wholesale costs are going to be and you know how many 'units' you plan on selling but with porn sites, the wholesale cost continually changes based on how many sites you build, how much content you have or add to those sites once they are up and running and also, the amount of units (read as memberships) being sold can fluctuate greatly.

When you start working out your profit margins on a specific site how do you go about working out wholesale cost, customer cost and sales volume?

Do you use figures for previous sites you have launched? What if you have never launched a site before?

In your opinion, what is the best method of working out profit margins for your adult sites?

Regards,

Lee