Ok, my balance sheet is only showing positive balances based on this query:
SELECT TblCustInfo.CID, TblCustInfo.Name, TblCustInfo.SrvAddr, TblCustInfo.SrvAmt, TblCustInfo.BLCAT, Sum([TblCharges.Chargeamt]) AS SumOfCharges, Sum([TblPayments.Creditamt]) AS SumofCredits...