@koroko, please forgive me if some of my comments seem redundant. Several postings were made to this thread while I was writing my response. I’ve edited what follows somewhat, but had already spent enough time on this, so I didn’t want to spend more on a more thorough edit.
First, if you are not, I strongly encourage using accrual-based accounting. I am not saying things will not work under cash-based accounting, but I can’t predict what strange things might pop up in various reports and displays.
I have spent a lot of time considering how to handle customer deposits in Manager. The issues are all the same, only in reverse. The problem comes when you start thinking of a deposit as being connected to an invoice. It is not. In your case, the deposit you make for Service B is not payment of an invoice or account payable; it is merely a repositioning of who holds some of your cash assets, in this case, to a supplier. So my belief is that you should not make any use of purchase invoices until you receive the invoice after the services are provided. Remember, an purchase invoice records an obligation to pay, which does not yet exist at the beginning of your month. It also records an expense, which has not yet been incurred.
In Manager, purchase invoices and supplier credits are all associated with obligations to the supplier, so it makes sense that any payment of a purchase invoice would be applied against that supplier’s account, and vice versa. After all, money is interchangeable. You acknowledged this when you said that your overall position with the supplier was being correctly recognized, just not the position on individual invoices.
Instead, a deposit should be allocated to an asset account. There are several options:
Create an asset account like
Deposits with suppliers. Allocate your advance payment to this account. This could be a convenient approach if there is only one such supplier, or possibly a very limited number. If more than one supplier, you will have to keep a separate record of how much of that account resides with each supplier.
Create similar asset accounts for each such supplier. But if there are more than a few, this will really clutter your balance sheet.
(My preferred approach) Create a custom control account. Then, for each supplier with whom you lodge deposits, create a subaccount. You will see only the control account on your balance sheet, but have individualized records within Manager of where every deposit went. [Note: I am not positive of how far the custom control account capability has been rolled out, and I don’t have time to test. Eventually this will work, but might not yet. In that case, use option #2 above temporarily. When the custom control capability is fully implemented, create the control account and reassign the individual asset accounts to it by editing.]
Any of these options will avoid the need of future-dated transactions, dummy transactions, or replacements. So your balance sheet will always be complete and current. All that is required is to use a journal entry to debit
Supplier credits or
Accounts payable when an invoice is received for Service B and credit
Deposits with suppliers.
LATE EDIT: I had time to test, and custom control accounts are not yet extended to accommodate this use case. So use option #2 for now and add the control account later. There will be no extra work involved and no data lost. You may just have a more cluttered balance sheet for a while.