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Answers (4)
@pclay
" Why base an estimate on a tax estimate known to be unreliable, as how often do people challenge the tax authorities to charge them more in taxes."
You make an excellent point and it highlights one of the major failings with the zestimate algorithm 'high loading' based on tax assessments compared to other factors. We all know that errors are made with tax assessments, and as you point out no one ever appeals a low assessment. As assessments in some counties are done every 7 or 8 years it means that zestimates during that period are wildly unrealistic and confuse the marketplace.
In the same way as zestimates are a starting point, tax assessments are only valid for the day that they were made. Using them to compute zestimates is pointless.
" Why base an estimate on a tax estimate known to be unreliable, as how often do people challenge the tax authorities to charge them more in taxes."
You make an excellent point and it highlights one of the major failings with the zestimate algorithm 'high loading' based on tax assessments compared to other factors. We all know that errors are made with tax assessments, and as you point out no one ever appeals a low assessment. As assessments in some counties are done every 7 or 8 years it means that zestimates during that period are wildly unrealistic and confuse the marketplace.
In the same way as zestimates are a starting point, tax assessments are only valid for the day that they were made. Using them to compute zestimates is pointless.

- pclay
- Contributions:3
Tax assessments are rarely correct. The value of a home, especially one that recently sold in a premium neighborhood in an area with a strong job market and economy like Arlington, should be based on the recent prices paid and for comparable homes in the same area, including internal and external upgrades that home buyers value, but tax collectors don't effectively value. Most will not complain about tax assessments lower than the actual value, as it is not to their benefit and the counties they live in tend to change the ratio collected per $ of value to meet their needs. The point was that the value of a Zestimate should try to accurately reflect the current value of the home (or the price recently paid), as many people use Zillow to compare home prices. Why base an estimate on a tax estimate known to be unreliable, as how often do people challenge the tax authorities to charge them more in taxes.

- Daniel and Tracy Pierson, "piersonteam"
- Contributions:3
If the tax data has incorrect square footage for a home or doesn't include the added value of a finished basement, for example, the value will not be calculated properly. Also, most tax assessments in Arlington are lower than the true market value, so that's a factor as well.

- Ritu Desai, "VARealtor"
- Contributions:697
Sometimes when Zillow does not have all the facts about your home it can have wrong estimate.
You can either correct the information or request a copy of comps from a Realtor. Last option would be to hire an appraiser.
You can either correct the information or request a copy of comps from a Realtor. Last option would be to hire an appraiser.
Why are the Zestimates so bad? Your estimates are way low for Arlington County VA - off by $100K+.
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