If you need to special order the items on a Sale for your customer and would like to create purchase order which duplicates their sale it’s easily done:

1. Click Copy and choose Create PO.
2. Select the correct vendor.
3. Click Save.

You can also choose to create a Purchase Order if you do not have enough stock to cover the order. This is easily done by right-clicking on the exclamation mark which will appear to warn you of your stock levels.