There are many ways to assign, evaluate and pay commissions. Almost every company has its own way. To be equitable Navision does nothing. [:)]
The commission percentage on the Salesperson/Purchaser table is a very poor tool. To meet customers’ needs some implementations are necessary. There are third parties’ solutions available around. In Italy I could name at least three - two of them developed by myself for two different partners. [H]
Anyway, you may try a solution like this:
build a table with salesperson code, item code, unit of measure and commission percentage or, maybe, commission factor - that is a number which, multiplied for the quantity gives the commission amount.
add a the commission percentage/factor to table 37, 111, 113, 115, 6661 being sure to use the same field number
on table 37 add a function which looks up the the commission percentage/factor in the above said table and have it executed in “No.” and “Unit of Measure Code” VALIDATE triggers.
write a report that evaluates and prints the commissions due on a range of invoices and credit memos (credit memos may or may not - according with the company’s policies - cause commission withdraw)
This is just the simplest idea - from this starting point you and your customer may complicate it at will. [:)]