background: we give our clients estimates, then some get PO numbers and some dont. when we have a PO for a given estimate, we do the job and then convert the estimate into and invoice where the PO gets automatically populated.  

how do i get a list of all estimates with open POs (i.e. estimates that 1) have a PO number and 2) have not been converted to invoices)?

the easiest would be to use the find function but i cannot see a way to modify the available columns to add one for PO and Open Balance.

another option i guess would be to use a report and modify it, but i am not sure which report to use.

any suggestions?

thanks