How can I make percentage rates in Pro Sites?


I am looking for a new payment solution for Pro Site. Normally, customers can pay a fixed monthly amount. You have the opportunity to stagger that monthly.

But I want only a variable monthly amount.
This derives from the payment options.
First and foremost I am thinking of Market Press. I want for example five percent of the sales from my clients.
Thus requires a separate entry field in the database and in the pro site. Market Press lists the sales in the database with the date.

The Store Statistic shows it. Thus, one can calculate the monthly revenue. This can generate an invoice. In my vision I see a a bill in which the site is specified by the Blog/Site ID of the customer
,name and address of me and the user ,a period description and services sales.
(Alternatively , split payment options , such as pay -per-view or Membership.)
Also a requested amount including VAT. That bill solution seems to be possible with Pro SITE very easy by editing.

The amount appeared then at the end of the month as a buttonfield with text. The customer is obliged to pay this. As with Pro Site when you can start a monthly payment. If the client is not paying then market press is for him and the customer no longer visible.

In summary:
I need the option of variable payments according to percentages in Pro Site. These arise from the monthly sales of the stores.

Can you help me?

The answer seems to be in the marketpress-stats and in the payment modul in Pro Site.