Second point - if the addition is not in the tax record then was it constructed with a permit? If it was, then you need to get that fixed from the county. It will change your assessment and you will pay higher taxes, but that tax value is what buyers are looking at...even though it is not he value of your home.
Don't try to figure out appraisers right now - the new HVCC law is screwing up the market. Appraisals are coming in low across the board - hard to build prices back up when appraisals are coming in for less than what the last home sold for.
For tax appeals in Fairfax County, you can go online to http://www.fairfaxcounty.gov/dta/realestatetax_home.htm. Follow the links to the form for an appeal. Complete the form and submit it as directed. My question to you is are you talking about a refinance appraisal or a tax assessment?
It is interesting to read (in that same site) how assessments (the value used for taxes) are calculated on the previous year's sales prices of homes in the area. The Herndon area has had a lot of distressed sales and that may or may not have affected the comps used by the appraiser. It is not supposed to, nor is it supposed to affect the assessments.
As noted previously, you should not hope to recoup the cost of an addition in the value of your house. A good report to read about this is the annual Cost vs Value report in Remodeling magazine. You can find it at www. remodelingmagazine.com.
Without looking at the house and the comps, I cannot offer an opinion about sales price or value.
Mary Margaret Gates
If the comps all have 3 bedrooms and 2 baths above grade (like yours), it really makes no difference if there is a bedroom in the basement. But if the comps have unfinished basements or if they're not walk-outs, your home's value should be adjusted accordingly. If you really feel that your house is worth more, it's up to your agent to find and adjust comps to support a higher price.
By the way, the tax records have nothing to do with the appraisal - and the last thing you want to do is have a higher assessment for purposes of calculating your real estate tax. Also, whether or not the bedroom has a walk-out or a closet makes no difference - under the Virginia building code, it simply needs a window or door large enough and low enough to provide egress.
First you can go to the township and ask them to update their records. You can also have a Realtor do a Comparative Market Analysis to challange the appraisal. However, keep in mind that because the addition cost you 180,000 does not mean that your home is now worth 180,000 more. Also,a bedroom should not have a walk out to the yard to be considered a bedroom. I hope this helps you. Good luck.
Coldwell Banker Flanagan Realty