Recently I looked at the PHP code called pillow. In fact it looks cool and seems to work.
You can also get comparable sales for a property using this library as I have shown at my demo page.
There is a small bug you need to fix before this will work.
You can see the comparables as shown in the above demo.
Using the latitude and longitude, you can map them on Google Maps - if you know how to program Google Maps - Check out my full blown demo.
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