I would neither copy nor move the attachment.. instead i would create a related list on the request table that queries the attachment table.. where the item the attachment on is a task for that record...
you have the sid of the item.. so you can get it then just dot walk up to the requested_item.request and if it is the same show it... this way you don't have two copies of the attachment.. and if someone deletes an attachment it goes away... i don't like hving the same attachment on two records.. they always end up out of synch
