What's the value of my condo?

The best way to determine the value of your home is to use the information an agent would in a CMA (comparative market analysis) that looks at a) the market activity history in that building, and b) similar unit sales in other buildings in that area, combined with the market knowledge and sales experience that a good agent has - which is not to say that you don't have all of those things, but if you don't, I would be misleading you to say that they aren't necessary in order to come up with the most accurate estimate of your home's value.

Zestimates are unreliable, as numerous posts on this site have attested to.  Appraisers are less focused on exact market value - they use predetermined value points based on specific criteria and their primary goal is to determine that the bank is not over-lending on the loan amount. Agents are the ones who are there from the pre-listing pricing stage to seeing how much money a buyer is actually willing to part with for a property, which is the true definition of market value. They have a lot more at stake as far as coming up with the value a home will actually sell for, and they are also more likely to factor in intangible factors that mean a lot to buyers (i.e., high ceilings versus low, good natural light versus poor light).

In your building there are only two closed sales that show up in the MLS - the 2000 sale and the penthouse unit in 2005 for $765K.  Knowing the sale price in 2000, and seeing as we are back to pre-2005 pricing and the penthouse would have sold for more anyway (barring something unusual about it), the Zestimate in this case could actually be a reasonable datapoint for a starting price estimate for your unit.  For more detail, which you would definitely want if you were going to list, you'd want information on comparable sales in other buildings, and I'm sure you know things about the unit listings that were cancelled in your building over the years that could help any agent who was pricing your unit come up with a more definite answer.  Hope this helps.

And the reason that the accuracy of the Zestimate can be called into question is that Zillow has no idea if you have made any improvements to your home or, for example, rented it.
My suggestion is that you look at the trend graph for your neighborhood and see what the change has been since you purchased the home in 2000.  Now use that same % change to your original purchase price.
This is simply another way of checking the value and this number should fall within the Range described by Zillow for the Zestimate of your home.
If your inquiry is a simple note of curiosity this will be accurate enough.
If you are considering refinancing your loan the lender will do their own appraisal and the Zestimate is not relied upon by the lenders.
If you are considering selling your home, I can do a CMA for you.

Hi Anne -

It has a current Zestimate of $578,600 here. Just a heads up, Zestimate is just a starting point to know a property's estimated market value. To get the appraisal value, its best to get a professional appraiser or do a CMA.

Thank you.

Neil
Zillow Customer Support