Doesnt work so well in new areas either. In new tracts the builders give owners options but typically record sales and the standard plan for a given model. For example a 2500 sf 4/3 with 3 car garage was available in my tract but most people opted for 2700 sq 5/3 with 2 car garage. Zillow uses what is in the public record and unless the homeowner edits the facts that difference throws off the zestimates by 5 to 10% alone.
