I imagine not all shops do this, but we serialize bikes when they are built (it's our way of looking at the item in backoffice and knowing if it's been built yet). It might be kinda nice to have an added field in an item's back office page stating whether it's boxed or built. Alternatively, if a bike is serialized when receiving the shipment, then there could be a confimation checkbox to confirm that the serial number is infact correct once it has been built. Redundancy is nice :)