VAT exception report

We have a customer who when setting up stock items has not selected the correct VAT rate on certain items. This has resulted in him creating some multiple item invoices with some incorrect VAT rates. We spotted this by checking that 20% of box 7 did not equal the VAT in box 1. All their sales are 20%. To locate the incorrect items is difficult, we actually exported the data to spreadsheets. Could you produce an exception report on the VAT return showing transactions that are at a different rate or where there are multiple rates on the same invoice? The Sage 50 reports on VAT exceptions work well.