Groups, subtracting, subtotals

[JZB-KRG]

I have this balance sheet which consists of three columns: account number, account name and amount. I’ve made some Custom Groups (e.g. account no. 1 to 5 is one group, no. 6 to 12 is another, etc.) so the end result is more like the yearly statement (I’m still working on some of the subtotals).

Now I’m asked to make some changes, so that the order is altered.

I need account no. 1+2 grouped in line one, account no.  1+2-3 (notice that account no. 3 is subtracted from 1 and 2) in line two and  account no. 3 in line three and a subtotal in line four. How can I do that?

If you need any other information please tell me. Thanks.

/JZB