With all the information out there avaiable to home sellers and home buyers, finding and getting the right information becomes a challenge.
Zillow is one of the most well known property valuation websites, but if you are using it to decide what to place your home on the market for or what the home you are looking to buy is worth you will getting inaccurate or irrelevant information.

This is a portion of the Zillow Data Coverage and Zestimate Accuracy graph. As you can see in Bristol County they are only within 5% of the sale price 24% of the time. That number is not good odds for either a seller or buyer to accurately price their home. In Plymouth County it goes down to 22%.
Definitions
Zestimate Accuracy/Star Rating: This rating is tied to the Median Error in an area.
The ratings are as follows:
-
= Best Zestimate
-
= Good Zestimate
-
= Fair Zestimate
-
= Tax assessor's value, or unable to compute Zestimate accuracy
- 0 stars = No valuation
Tax Assessor's Value
Depending on the jurisdiction where you live, this value could be the tax assessed, tax appraised, or market assessed value. This value comes from the taxing authority of the city, county or state where you live; this is not Zillow's value.
Note: Tax assessor's values differ from Zillow's Zestimate, which is computed by entering numerous data points into a proprietary formula, often resulting in a more accurate value estimate.
Homes on Zillow: This indicates the percentage of homes for which we have data (e.g., number of bedrooms or bathrooms) in a particular locale. These are the homes you can find via maps or search on Zillow.com. Homes With Zestimates: We can only calculate Zestimates for homes where we have certain data, including transactions. This column indicates the percentage of homes in an area with Zestimates. Within 5% of Sale Price: This is the percentage of transactions in a location for which the Zestimate was within 5% of the transaction price. For example, in the Portland area, 30% of the time the Zestimate was within 5% of the selling price. Within 10% of Sale Price: This is the percentage of transactions in a location for which the Zestimate was within 10% of the transaction price. Within 20% of Sale Price: This is the percentage of transactions in a location for which the Zestimate was within 20% of the transaction price. Median Error: Half of the Zestimates in an area were closer than the error percentage and half were farther off. For example, in Seattle, Zestimates for half of the homes are within 8.2% of the selling price, and half are off by more than 8.2%.
As you can see from the legend I pasted above they rate their own ability to be accurate. In Plymouth County they gave themselves 2 Stars which is Fair accuracy. For easier understanding to me that is a D. My son would have been grounded for months if he ever came home with a grade like that.
If you are a home seller or home buyer and would like an accurate Market Report please contact me and I will give you a no obligation report on your home or a home you are looking to purchase.

Zillow has an even harder time getting close to accurate numbers in Texas because we are an non-disclosure state.