too ambiguous?

lemme sup up

I have columns on the DEALS sheet where we enter the deal data/.... such as date, customer, stock #, etc.

When there are 2 salesman, the deal gets split, and each salesman gets half of the gross or unit for that deal. I want to keep the data entry super basic and idiot proof... so I want the sheet to do all of the work. I need a formula that can look at a range of rows on the DEAL sheet, and give me data based on a match in EITHER column F or G... but sometimes with multiple criteria.

So if I need to count how many New cars James sold that were Leased, but I want a 1 when he's the only salesman (his name would appear in column F, and G would be empty) or 0.5 if there is another salesman in the row. ( he could be in column F OR G). There is a column that indicates New or Used with an N or a U; also a column that indicates (C)ash (F)inanced or (L)eased vehicles.

I want the result to total all cars(rows) that match his name (Staff!AA6) and then live on the STAFF sheet (AY6). See the above post's attachment for how I solved it.. I just think what I'm doing can't be the easiest way.

can you see a simpler way of counting given the split deal issue?