I'm having a similar problem.  A former unit owner, marked inactive,  shows up when I run a detail balance report.  I ran a report to see all open balances (current year), but she doesn't show up there.  I changed the open balance criteria to "All", and again she is listed (despite being marked inactive) but there is no balance.  So I ran another report to see every transaction for all time. All her prior transactions are properly paired (invoice to payment, credit memo to invoice), and there is a zero balance. 

So why does she keep showing up?