David (and Jay)
It is based on 34 years of experience as a residential agent, viewing the same comparables that an appraiser uses, that allows me to evaluate the statistics and offer my expertise.
It is clear, as an agent in the trenches, what market factors come to bear on values. When you work in an area, you can look at prices and hear the feedback of real clients to know what affects value in their eyes.
Market value is based on the assessment of a willing buyer and a willing seller. Appraised value is a different valuation altogether.
While not minimizing the importance of the appraisal, it serves a different purpose than a CMA, which attempts to evaluate how a property is perceived by a willing buyer and a willing seller. You can then make use of these statistics to determine both offer price, and, as a seller, projected market time and value. Nothing is foolproof, and other market factors come in to play, as well. As I initially said, it is very property and school specific.
It is unrealistic to expect Jay to obtain an appraisal on a property he may not intend to purchase. It is, however, completely reasonable for Jay's agent to be able to prepare a CMA to assist him in the decision-making process.
Jay was not asking about "parks, golf courses, shopping centers/strip malls, major roadways, etc." He was asking how to ascertain value and noise/ traffic when the school is not in operation. His question was valid and clear. Jay, I know my answer will assist you.
Best of luck,
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