RE: Purchase Order number with Project ID
Maybe enter a purchase pool on those purchase orders for POs that are for projects.
A minor refinement is to create a new PO pool; for the project related orders for each new fiscal year e.g. P17, P18 etc.
This is currently an optional memo field only. Not mandatory, no validation etc, but it can be very useful for filtering, sorting, grouping etc.
One possible challenge is that you may sometimes buy to project, and at other times buy centrally to inventory and then issue items from the same PO either to several different projects, or also for other inventory transactions.
In general I prefer to buy to inventory to a project warehouse i.e .one warehouse per project and then issue as required either to project requisition, or to specific wbs lines Otherwise the full installed quantity is booked direct to Project wip at project header level, there is no visibility of any excess inventory, and the inventory is not booked by WBS line .
If you define a project warehouse for each project, with a prefix PW1, PW2 etc, then maybe you can filter all POs raised/ received for warehouses PO*. You will also then be able to track all project inventory issues.