20. Any quotation that includes an increase to operating costs (e.g. maintenance or utility costs) should be closely scrutinised to ensure that any reduction in the existing costs is taken into consideration. For example, where a new system is introduced that replaces an existing system the maintenance costs associated with the existing system should be deducted from the price increase. It should be remembered that "maintenance costs" includes the provision of spares and that any savings the contractor makes from not having to provision spares for a system that has been replaced should be reflected in the contractor's quotation.