Order Cancel Option for Unavailable Item

[Jobin Jose]

Hi everybody,

I am new to VM , I faced a situation like ..
 
  When an order has been placed with more than one item(or 1 item). if any of the item is not available in the store we can go to the admin panel and change the status to ( refund). But instead of this i need a new invoice or edit the current invoice with current updation. that is if the admin select refunded then the total amount of the invoice needs to changed and the product status shows as per the status. any help ??
Vm Version : VM2.0.6
Joomla       : joomla 1.7
Thanks in advance ..