We had an unfortunate experience where a typo in the FMV field caused all receipts with that item to have the wrong FMV. As a result, we had to send revised receipts to everyone who had purchased that item (there were many available for purchase). Allow the FMV to be changed at any time in the event there is a typo. Patrons who had already bid on the item could be sent the option to review the change and retract previous bids if they desire.