In our old, non-DBA system, we have a few parts on our bills of materials that are customer supplied.  These were handled badly and outside of proper channels.
 
How do you recommend handling these situations (read: Are not purchased but need to be inventoried, received and issued on WOs) per DBA best practices?
 
i.e. Are they set up as type R items with zero costs? Do they need to have 'bogus' POs created to create something to be received against? List customers as vendors? etc.  Your recommendations would be most helpful!

We have handled a couple of parts this way in DBA for four or five years and it works very well.