VO is a variation order occurred when the project owner request some modification in the specification, drawing, or something else which cause a noticeable variation in the bill of quantities, also it could be due to a Force Majeure like COvid19 lockdown, in these cases the main contractor claim for a variation cost and time (variation order), while the VE is a value engineering that can be done by the contractor or a third party (consultant company) to re-valuate the project cost by removing or substituting some materials by an alternative or conduct some minor modification in the drawings to increase the project cost