After clicking Prepayment, a window will pop up, asking for you to enter details regarding the prepayment (see Figure 3). In the Description field, enter the description of the prepayment that you’re creating, and then click the prepayment basis that you wish to apply.
After you set up the prepayment basis toward a particular purchase order, you can then post the prepayment. To do that, go to the Purchase Order header, then to the Invoice option, and click Prepayment Invoice (see Figure 7).