Site Valuation and the Cost Approach: Where Real General Appraisal Work Lives
By Appraisal Institute
Walk into any review meeting on a complex commercial assignment and watch what happens when the cost approach comes up. When an appraiser treats it as a checklist exercise, with a Marshall & Swift lookup, a few depreciation deductions pulled from the air, and a reconciliation paragraph that hand-waves the result, the report falls apart under scrutiny. But if the cost approach was developed with the same rigor as the sales comparison and income approaches, the report holds. That difference is what the course “General Appraiser Site Valuation and Cost Approach” is built around.
There is a persistent idea amongst appraisers that the cost approach is a fallback, the method you turn to when comparables are thin or income data is incomplete. It is an old reliable habit, not a valid argument. For new construction, proposed improvements, special-use properties, and any other assignment where functional or external obsolescence is doing real work in the value conclusion, the cost approach is not a backup. It is often the most defensible analytical path available. Hospitals, schools, manufacturing plants, religious facilities, owner-occupied industrial buildings: these are all properties where you cannot pull six closed sales from the last twelve months and call it analysis.
The course starts with site valuation because that is where most appraisers, including experienced ones, have the thinnest applied skills. Identifying a few land sales is not site valuation. Site valuation begins with a defensible highest and best use analysis of the site as if vacant and available for development. From there, the appraiser has to choose among the six recognized methods (sales comparison, extraction, allocation, subdivision development, land residual, and ground rent capitalization) based on data availability and the characteristics of the assignment. Extraction in particular is one of the more useful and undertaught methods. When you can defend it, it gets you to a credible site value in markets where vacant land sales are scarce.
The cost approach material follows the same logic. Reproduction versus replacement cost is not an academic distinction. The choice you make determines what depreciation you have to measure. The course works through the major cost-estimating methods (comparative unit, unit-in-place, and quantity survey) and the recognized cost data sources, including Marshall & Swift and RSMeans. It then turns to depreciation, which is where most cost approaches either succeed or fail. Physical deterioration is the easy element of the equation. Functional obsolescence requires judgment about how the market actually responds to design and utility issues. External obsolescence requires the appraiser to measure something the market is doing to the property from the outside in. The case studies take this from theory to practice, including an industrial assignment that runs the full sequence and a residential site valuation problem that pulls extraction and sales comparison together with professional cost data sources.
For candidates pursuing the certified general appraiser credential and the MAI designation, this is required education. It earns hours toward the path, but the more substantive value is that the analytical habits the course builds, including disciplined site valuation, rigorous depreciation analysis, and defensible reconciliation, show up in every general assignment that follows. The path is demanding because the work is demanding. This is one of the courses that helps prepare you for it.
The June session runs Monday through Thursday, June 15 through 25, from 1:30 p.m. to 5:00 p.m. Central. The afternoon format lets working appraisers stay productive in the morning and bring real-world questions into the classroom. The instructor is Diane Viggiano-Gavin, MAI, AI-GRS. The general designation and the review specialty together mean she has seen the cost approach developed correctly and developed poorly, and she teaches accordingly.
AI members receive a discount on education that adds up over a multi-course QE path. If you're working through requirements, the math on membership pays off quickly.
If you have been treating site valuation and the cost approach as something to get through, this is the course that will change how you think about both.
Ready to build a more defensible cost approach?
Register for the June 15-25 Session
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