In Teledyne Continental Motors v. Muskegon Twp, 145 Mich. App. 749, 756; 378 N.W.2d 590 (1985), the Court held: Clearly, the replacement cost approach does eliminate the need to calculate some types of functional obsolescence. By definition, replacement cost eliminates functional obsolescence due to excess construction or superadequacy. However, a determination of other sources of functional obsolescence, not caused by excess construction, must at least be considered in the replacement cost approach. In the present case, the tribunal ruled that all functional obsolescence is eliminated by use of the replacement cost approach. This amounts to an adoption of the wrong appraisal principle. The tribunal should have specifically determined whether the sources claimed as functional obsolescence by the petitioner are in fact eliminated by use of the replacement cost approach. This is primarily a factual determination based upon a determination of fairness in each particular case, and we therefore do not presume to suggest a proper result. On remand, the tribunal may well determine that the elements of functional obsolescence claimed by petitioner are not proper factors to be considered in calculating replacement cost.