Q: Can I take the cost of changing from an incumbent into account in an evaluation?

A: Yes, provided that the tender documentation is clear as to how costs will be evaluated, and that the evaluation is not structured in a way which would give rise to unequal treatment (eg, it would not be appropriate to use a separate criterion, with points available, for "cost of change"). Incorporating the cost of change into evaluation of whole life costs is legitimate where this reflects the costs to the contracting authority of appointing the relevant bidder.