Many mature companies make far too many changes to “reduce costs, save time, save material” when, in fact, they do not know if that will happen. A payback standard needs to be set—a length of time wherein you expect payback to occur. Probable change cost needs to be estimated on some requests/changes. Estimating payback doesn't need to be done on all changes, only those changes with doubtful payback. If you think estimating the change cost payback is expensive, try not estimating the payback. Accounting needs to furnish labor and special overhead rates for ABC cost estimating. The change team and CM need to make the estimating routine fast—and it need not be expensive.