4.14 Validating benchmark data is a complex and specialised task and most contracting authorities are unlikely to have the necessary expertise. They will therefore need to appoint experienced technical advisers. As well as validating / agreeing the unit cost increases, the impact of these adjustments have in the project companies financial model must be demonstrated over the remaining life of the contract. The practical application of updating the financial model (assuming that this is required and economic) will be in accord with the financial model/unitary charge variation mechanism requirements. It must be ensured that parties are left in a no better no worse position after allowing for the change in price relating to benchmarking.