I'm not a trained bookkeeper, just helping with a backlog of Purchase paperwork into Sage 50 (which I don't know how to use). If you have the patience to help (thank you) and assume I know nothing - you won't be far wrong.
The company makes a cheque payment to DART for crossing the bridge. Receipts for the crossing come in (on a statement of account). Normally, supplier invoices would be posted and payments made from Bank. However this is backtofront as I need to make a payment from Bank and then allocate supplier receipts.
When you initially enter the payment, enter it as a supplier payment - but since it's a payment in advance there will be no invoice to match it to, so when you tell Sage to save it, it'll pop up a warning; accept it and the payment will be saved as a "payment on account".
When you enter the invoice, you post it to the same supplier account.
Now you can go back to the supplier payments screen. You don't need to enter an amount. You'll see the unmatched payments and receipts - select the payment (go to that line in the screen and either press 'Ctrl P' if you are able to allocate the whole amount, or enter an amount in the empty field on the line to allocate part of it. Then do the same for the invoice - 'Ctrl P' will select the whole amount, or you can enter a lower amount.
The important part is to make sure the amount you're allocating zeros out; don't allocate any more than the amount of the payment, otherwise you'll be entering an additional payment: i.e. the total payment needs to show as zero on this screen before you save.
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Vince M Hudd - Soft Rock Software
(I only came here looking for fellow apiarists...)