When should I use Payment Adjustments vs. PO Addendum?

The key indicator on making a Payment Adjustment or creating a PO Addendum is going to be if there is a change in the scope of work. If the vendor is needing to do additional work, that would be a new WO and then you can create a PO Addendum to the original PO.

Payment adjustments are going to be used if you just simply need to true up your dollar amounts to keep them inline with your accounting system. Example: If a vendor invoice comes in slightly off from your original PO, you can create an adjustment, that is either positive or negative amounts, to show the actual cost.