5.70 The prospective lenders should have carried out broad due diligence at the time the Final Tenders are submitted. However, full technical due diligence and detailed negotiations on term sheets will need to be progressed at the preferred bidder stage. It would be disproportionately costly for all funders to undertake this level of due diligence prior to submission of Final Tenders. These aspects should therefore be capable of being dealt with following appointment of Preferred Bidder providing that they do not result in material changes to the tender, distort competition or have a discriminatory impact. As far as possible, any cost impact arising from the funders due diligence should be processed through a preagreed costing methodology to ensure that there is no distortion of competition.