SQL - Get AR / AP Balances

DECLARE @LastClosingDate as datetime
DECLARE @ClosingDate as datetime

SELECT @LastClosingDate = '2014-12-31',
		@ClosingDate = '2015-12-31'

SELECT
 Account
 ,Name
 ,HomeOpening = (SELECT SUM(Debit-Credit) FROM PostAR where AccountLink = Client.DCLink AND TxDate <= @LastClosingDate)
,
ForeignOpeningBalance = CASE 
WHEN bForCurAcc = 1 THEN (SELECT SUM(fForeignDebit-fForeignCredit) FROM PostAR where AccountLink = Client.DCLink AND TxDate <= @LastClosingDate) 
ELSE 0 END 
,HomeClosing = (SELECT SUM(Debit-Credit) FROM PostAR where AccountLink = Client.DCLink AND TxDate > @LastClosingDate AND TxDate <= @ClosingDate)
,ForeignClosingBalance = 
CASE WHEN bForCurAcc = 1 THEN (SELECT SUM(fForeignDebit-fForeignCredit) FROM PostAR where AccountLink = Client.DCLink AND TxDate > @LastClosingDate AND TxDate <= @ClosingDate) 
	ELSE 0 END 
,ForeignClosingBalance = 
CASE WHEN bForCurAcc = 1 THEN (SELECT SUM(fForeignDebit-fForeignCredit) FROM PostAR where AccountLink = Client.DCLink AND TxDate <= @ClosingDate) 
	ELSE 0 END 
FROM Client

SELECT
 Account
 ,Name
 ,(SELECT SUM(Debit-Credit) FROM PostAP where AccountLink = Vendor.DCLink AND TxDate <= '2010-12-31') as HomeOpening
,
CASE 
WHEN bForCurAcc = 1 THEN (SELECT SUM(fForeignDebit-fForeignCredit) FROM PostAP where AccountLink = Vendor.DCLink AND TxDate <= '2010-12-31') 
ELSE 0 END as ForeignOpeningBalance
,(SELECT SUM(Debit-Credit) FROM PostAP where AccountLink = Vendor.DCLink AND TxDate > '2010-12-31' AND TxDate <= '2011-09-30') as HomeClosing
,
CASE 
WHEN bForCurAcc = 1 THEN (SELECT SUM(fForeignDebit-fForeignCredit) FROM PostAP where AccountLink = Vendor.DCLink AND TxDate > '2010-12-31' AND TxDate <= '2011-09-30') 
ELSE 0 END as ForeignClosingBalance

FROM Vendor