Mike, I have the Holy Grail!
Pssst...(the magic list exists). I'm looking at it right now, yellow as it is with age. Its titled "Basic-Adjustments - Based on past paired sales analysis and experience (not engraved in stone)". It was given to me in a secret ceremony of passage into the mortgage brokerage ownership world in another life of mine. The legend goes that It was passed from Fannie Mae to UW's to be able to check appraisers rang of grid adjustments (only an unconfirmed legend).
It has topics on the left side from top to bottom: LOCATION, with sub topics: Busy traffic street, Semi- busy traffic street, Backing to external obsolescence. QUALITY OF CONSTRUCTION, BV versus Alum., Alum vs Frame/Asbestos, Alum. vs Vinyl/Stone. Other Topics are: Age, Condition, Room Count Adjustments, Bath Count Comparisons, Square Footage Adjustments (per price range), Basement Area (Comparing Slab vs Crawl, Bsmt vs No Bsmt, WalkOut vs No WalkOut, Finished vs Unfinished), Heating & Cooling (FWA vs Elect,Gas HWBB, etc.), Garages( 1 vs 2 vs 3 etc.), Energy Efficient Items (windows,solar, etc.) Fireplaces, etc., and etc.,
It needs to be adjusted for inflation. It has four columns running from left to right: $30,000 to $50k, $60k to $100k, $100k to $200k, $200k to $500k, with different adjustments in each column depending on the price price range. Nothing on manufactured homes.
It came into my possession about 1988 although I didn't use it until I sold my interest in mortgage operation and opened an appraisal business in 1992. Someone has put a lot of time into extracting the data. I've double checked and tried to prove it wrong but threw the years that I and my staff used it in my little appraisal company we never had one single adjustment questioned. In the process for rounding the dollar amounts in the grids in seems accurate enough for government work!
(Mike, I always reply...there is no magic list). Yes, thats want I told my trainees as I trained them. I wanted them to learn how to do it the right way first. Years later when they graduated, I passed the "magic list" on to them, (some were pissed).
Mike, I'm sixty years young and finally learning to never... say never, and magic can happen!
Watchyourtopknot,
Florida B) Jerry