I use the budget tab to calculate P&L for each contact and divide out commissions.
I often advance portions of commissions to sales reps.
It would be great if I could add a negative - number as commission in the budget.
Avco Roofing commented
we do the same thing. to do it I add another payout and label it "Draw" - I keep the original commission so that it keeps calculating all the way through the close of the job. after the payments and expenses are confirmed I add a new commission that equals the commission calculated minus the first draw. after that I delete the auto calculated commission and am left with 2 payouts on the job. Hope this helps.