While Zillow may be a place to start when determining a home’s value (called a Zestimate) it is not a good place to end!  Consider their own most recent statistics from June 15, 2011 for the San Francisco Bay Area:

* Their median error on all Bay Area home appraisals is 7.2%.  That’s almost $40,000 off on a $500,000 home

* Two-thirds of their home appraisals in the Bay Area are off by more than 10%

* One-fifth of all “Zestimates” are off by a whopping 20%

By simply averaging large amounts of Tax Roll data, Zillow cannot get the full picture.  It misses nuances like neighborhood, street location, school district and any amenities added to a home (i.e. remodeled kitchen, new deck, pool, windows, baths, or floors.)

While it amy be a fun little tool, Zillow and other automated home appraisal sites simply lack the human touch to bring much credibility to the table.