In Accounts Payable, you have the ability to record the AP Invoice and Payment in one transaction from Manual Check Entry. You record the Invoice and Payment in one transaction.
In Accounts Receivable and Sales Order modules, you have to Enter the Invoice and then Post it. Then you have to enter in a Cash Receipt and Post it. These are 2 repetitive steps. Therefore, if you have 100 invoices and 100 payments, you now have 200 transactions to enter into Sage 100.
There are many times, customers want to record the Invoice and Payment from another system and the want it to reflect in Sage 100. It would be very efficient if there was a way to record the AR or SO Invoice and show it as PAID the in one transaction similar to AP Manual Check Entry.
by: Alain S. | over a year ago | General Enhancements

Comments
It makes sense, especially since there are fields within the invoice data entry for check number and amount. Usually we don't get paid until after an invoice/statement is sent, but sometimes we get payment upon delivery. I've entered the payment along with the invoice a couple of times, but IIRC, it doesn't track the payment date/check number like it does when using Cash Receipts Entry so stopped doing payments that way.
They should make a new section like AP Manual Check Entry where you can Create the Invoice and Input the Payment at the same time.
There should be a process where you can record the sale (invoice) and receipt (payment) at the same time. A new task should be created. Perhaps call it Sales Receipt.
Here are some use cases for this:
1. There are many companies that take a sale and receive payment on their website and want to record it in Sage 100
2. This would also be good for POS or other external systems as where the sale and payment are made in another system and you want to record these transactions in Sage 100