Even good sites may have certain tools that aren't so hot. Some sites may make you poorer. And sometimes the problem is you.
Don't: think that Zillow.com tells you what your house is really worth.
The "Zestimates" on this popular real estate site are based heavily on sales prices of comparable homes. So unless there's been lots of activity in your 'hood lately -- unlikely these days -- the value may not be very accurate.
Instead: Call an appraiser to size up your property in person.
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