
Marc D. answered 03/08/21
Engaging and patient Master of Applied Mathematics.
You would want to build out the monthly cashflows for each year. Put the years in the column headings, so 36 columns of data, 1 column of row headings. Add the expected cashflow without the margin for that month. Then build up from there as you go down the sheet, by adding the margin for each month and for each customer.
After that you would put in the costs, the splits, the vat etc. on a row by row basis for each month.
Total toward the end and you are done.
It's a bit much to describe in this format, but you could either schedule time with a tutor or look up some financial modeling courses on the interwebs. There are plenty :)
Good luck.