Advanced company settings
FollowAdding terms & details to purchase orders
For those users who clarify payment details with their suppliers through other correspondence, this can be done on your purchase orders.
Comments are entered while doing the purchase order, in the Comments field above the Product Entry Lines. Payment Terms are established on a supplier by supplier basis in supplier setup.
Finally, enter your payment details through Settings | Company

This means that when sending a purchase order to a supplier there will be a clearer understanding of the terms, details, and conditions of payment. Being contained in one document eliminates the risk of these being lost in transit when being sent separately.