->RetailVista -> Start -> Sale orders -> Generate purchaseorders.
Select the sale order(s) to make a purchase order out of it.
In the sale order it shows ‘Attached purchaseorders’. 
The purchase order will get the status ‘New’ and when you click on the ‘attached purchaseorder’ you will go directly to the purchase order.
The sale order will get the status ‘FinalAndInProcess’.
Please note that it is not possible to make a purchase order out of a sale order when the prepayment has not been paid or the payment has not been processed through the till or the backoffice.