How can an appraiser account for a property's deterioration?

An appraiser accounts for a property's deterioration by raising the effective age of the property. Effective age reflects the condition and usefulness of a property as determined by its maintenance, renovations, and overall state of repair, rather than just its actual chronological age. Deterioration indicates that the property is in less than optimal condition, which generates a perception that it may not perform as well as a newer property. By increasing the effective age, the appraiser is effectively indicating that the property has depreciated due to wear and tear, which should be factored into its value assessment.

In contrast, the other options suggest adjustments to the chronological or effective age that do not accurately reflect the impact of deterioration. Decreasing the chronological age does not take into account the actual condition of the property and can mislead stakeholders regarding its true state. Similarly, reducing the effective age would suggest the property is in better condition than it is, which would not convey the necessary information about its deteriorating state. Thus, raising the effective age accurately captures the property's current value in light of its deterioration.