UPDATE tDataCollection
SET tDataCollection.AmountExGST = DC4.AmountExGST,
 tDataCollection.GSTAmount = DC4.GSTAmount,
 tDataCollection.AmountIncGST = DC4.AmountIncGST
FROM (

SELECT DC3.*, CAST((DC3.AmountExGST + DC3.GSTAmount) AS money) AS "AmountIncGST"
FROM (SELECT DC2.ID, DC2.AmountExGST,
 CAST((CASE WHEN tDataCollection.GSTFlag LIKE 'Y' THEN (DC2.AmountExGST * 0.1) ELSE 0 END) AS money) AS "GSTAmount"
FROM (SELECT DC1.ID, (Max(tRate.Cost)/12) AS "AmountExGST"
FROM ((SELECT DC0.ID, DC0.ServiceID, (CASE
  WHEN DC0.TEC IS NULL THEN 0
  WHEN DC0.TEC = 'XX' THEN 0
  WHEN DC0.TEC = 'NN' THEN NULL
  WHEN DATALENGTH(RTRIM(DC0.TEC)) = 0 THEN 0
  ELSE CAST(DC0.TEC AS int) END) AS "Length"
FROM (SELECT tDataCollection.ID, tDataCollection.ServiceID,
 SUBSTRING(tDataCollection.Var09,2,2) AS "TEC"
FROM tDataCollection
LEFT JOIN tTransactionType ON tDataCollection.TransactionTypeID = tTransactionType.ID
LEFT JOIN tTransactionGroup ON tTransactionType.TransactionGroupID = tTransactionGroup.ID
WHERE tDataCollection.BatchID = 24299
AND tTransactionGroup.Description LIKE 'RENT') AS DC0) AS DC1
LEFT JOIN tServiceID AS SI1 ON DC1.ServiceID = SI1.ServiceID)
INNER JOIN tRate ON ((SI1.ServiceTypeID = tRate.ServiceTypeID) AND (ROUND(DC1.Length,0,0) = ROUND(tRate.Length,0,0)))
WHERE DC1.Length IS NOT NULL
AND tRate.Cost IS NOT NULL
GROUP BY  DC1.ID) AS DC2
INNER JOIN tDataCollection ON tDataCollection.ID = DC2.ID) AS DC3

) AS DC4
WHERE tDataCollection.ID = DC4.ID