Why did the trulia estimate of the house go down when I specified the square footage to be 1500 sq ft more?

Asked by Nick, Los Altos, CA Thu Jan 31, 2013

For some reason constantly appraises the value of my home based on 4,500 sq ft, even though the home is 5,957 sq ft. What proof do they need? I have the approved plans since I was the general contractor and I am the property owner!

This question was asked from this property: http://www.trulia.com/homes/California/Los_Altos_Hills/sold/…

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Terri Vellios’ answer
Terri Vellios, Agent, Campbell, CA
Fri Feb 1, 2013
Automatic valuations on line are not accurate. They may be pulling from tax records and they may not be updating their records. Even if they had the sq. ft. correct, a computer can not know the value because it has not seen the details of finish work, location, landscaping, etc.

As recommended if you are concerned about the sq. ft. Have someone check the tax records to see if that is correct. As a general you know garages or unfinished space is not calculated into living space. Even though there may be some value to a buyer the tax records won't show it as sq. ft.

What is your intention to knowing the value of your home?

Have an amazing day!
Web Reference:  http://www.terrivellios.com
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David Blockh…, Agent, Los Altos, CA
Thu Jan 31, 2013
The county records indicate square footage in the 4500 sf range not the 5700 sf range. Was the permit finalized? I suggest you start with the building dept in Los Altos hills to tract down why your home's size hasn't been updated on the county records.

Dave Blockhus
Coldwell Banker - Los Altos Office
650 917-4250
DRE #01169028
0 votes
Stu Carson, Agent, San Jose, CA
Thu Jan 31, 2013

Below is some explanation from Trulia on how they determine values. In it they admit there can be a 20% variance. When you changed your sq ft a whole different set of recent sales were likely looked at by their algorithm.

If you are looking for an accurate valuation of your home, let me know off line and I will be happy to send you a market value analysis in the next 24hrs!

If you are concerned about what value Trulia shows and want to try to correct it or "game" it, let me know, between us and Trulia, I think we can find a way to get it to be more accurate.

If you are thinking about getting ready to sell your place some time this year, you can learn a little more about me at these links

resume http://stucarson.com/AboutTheTeam

references http://stucarson.com/testimonials

Then call me so we can discuss how to achieve your specific objectives.

Stu Carson

"A Trulia Estimate is just that: an estimate of a home's worth. Our estimates use a ton of info, including recent sales of similar homes and home facts like number of bedrooms and bathrooms, square footage, and more to provide insight into what a home is worth. You can help us improve our accuracy by telling us what you think of your home’s Estimate, and by claiming your home and updating its facts... We measure accuracy by comparing (1) actual sales prices for recently sold homes over a 3 month period with (2) those homes’ Estimates at the start of that 3-month period. For each county, we report the median error of these differences and the percentage of sales where Trulia Estimates were within 5%, 10% and 20% of the final sale prices...."

The above and more can be found at Trulia's website at this page http://www.trulia.com/trulia_estimates/
0 votes
Thank you for your detailed response Stu. (An aside - My Wife's last name is Carson).
Los Altos Hills had odd building codes in 2002 when I got the house approved. At the time the max sq ft I was allowed was 5000 sq ft, but I could have a basement. Since 1/4 of the downstairs is built into the hillside, I was able to getting the house approved by specifying the downstairs as a basement (since it fit their guidelines at the time). The true square footage of the property is 6417 sq ft (400 sq ft garage included in the 6417).
The county records use what Los Altos Hills gave them (4500 sq ft (not including garage)). I just like to have the house fairly appraised for this is important whenever I refinance my mortage or may sell the home in the future. The estimate also does not take into account that the house is made out of Insulate Concrete Forms (ICF) so it is extremely quiet and built to last for 300-500 years as opposed to a wooden framed home.
Flag Fri Feb 1, 2013
John Juarez, Agent, Fremont, CA
Thu Jan 31, 2013
I suspect that the automated valuation that is making you unhappy is based on information in the public records despite your assertion that those records are substantially incorrect in regards to the size of your house.

I find valuations such as this to be items of curiosity, only. Anyone can type in an address to one of the valuation sites and get back a figure on any house in which they have an interest. Whether the interest is legitimate or one of curiosity, only, is unknown. Personally, what others find about the value of my home is not of importance to me.

If, however, I wanted to know the MARKET value of my home because I was planning on selling it or borrowing against it I would talk to the experts…Realtors or appraisers…and not worry about what an automated valuation site says.
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