Invoice blocking due to tolerance limit at header Invoice Value.

Hi,

Our client needs to have tolerance limit set for total Invoice value.The Invoice contains multiple line items.The tolerance may be % or $ value.The standard setting which I know is for each Invoice line item but not for cummulative.The issue is if we post exceed but within tolerance amount for each line item from the Invoice containing multiple line items,the total Invoice value exceeds considerably.

Please let me know the how to deal with this issue?