Hi Linda
You could rely upon the Recovery of Imposts Act and set up a series of letters asking the owners who have been overcharged to provide evidence by way of receipts for payment to qualify for any refund from 1993 onwards – the issue you may have with this is locating all owners where there has been a sale.
If evidence is submitted to Council and such evidence (receipts) is acceptable (payment within a 12 month period) then Council should refund those moneys but only to the name or entity on the receipt.
Further letters should be sent confirming a refund or declining a refund.
Regards
Mel