[development-axapta] Payment in advance

[staffuwa]

Hi Guys,
 do you know how to handle a "Payment of a Cust/Vend Order in advance" ?? 
In other words:
if I create an Purch Order and I want to pay it for 10% at the
creation of the order and for the remain when the items are delivered,
how can I handle the situation ?
Thank you very much.
Daniele.