They don't, or at least they shouldn't. Zillow is the big one and if "cookie cutter" neighborhoods where homes are the same s.f. and style they actually do well on value. But if you get into an area with a variety of home styles they don't do well at all.
Assuming you are working with a Realtor you and your Realtor should review a detailed comparison of recently sold homes in the neighborhood where you are buying and rely on that information plus the condition of the house to determine a fair offer price. Best of luck!
listings on the internet. A residential appraisal or an competitive market analysis of the home using the most recent sold data is the only reliable measurement of home value. Understand this, you can have 3 appraisals of the same property with-in the same week with different valuations on the same house. This is a people business and not every appraiser will see the same house the same way.
RE/MAX Realty Group
There are a number of automated valuation sites and I wouldn't rely on any of them. They are based on the most general data of age, size, room count, etc. but can't factor in condition, updates, deferred maintenance etc.
Buyer's who use these sites as their guides are getting lousy advice. Zillow admits to not being a final value, but a place to start.
As you look at all the homes in a certain neighborhood, size, etc. you are a more reliable guide to values than these sites. As some home disappear and new ones come on you see the level of activity in the market and which homes are selling and which aren't.
Trust your realtor, the CMA they provide and your own eyes more than any of these sites.
The value estimates on these sites do not impact potential offers. I'm sure you remember that all real estate is local. For structuring an offer, you want to access the comparables on sold homes most like the property you are interested in in the area of the potential purchase. These sites aggregate data and are not reliable when it comes to individual properties.
If you are ready to make an offer, talk to an agent you trust. He or she will be able to give you a value range, with supporting detail, for an offer as well as tell you what recent closed sales on like properties have been down to an offer % level.
I work in the Mount Airy area as both an agent and an appraiser and am familiar with homes in that area. If you don't have an agent, give me a call or send an email. I will be happy to help you.
if you are working with a Realtor, they will assist you in preparing an offer. They will also provide you a CMA or Competitive Market Analysis of recent sales & active listings for you to make an informed decision on how you want to proceed with your offer.
If you are financing your next home purchase keep in mind you will have an appraisal thus your lender will only provide you a loan where with appropriate value.