Cross-check real estate listings with shapefiles?

Question

I am starting to explore ways to cross-check real estate listings on sites like zillow, redfin, etc. with shapefiles in ArcGIS Pro or Online. Specifically, I want to be able to automatically be notified if a real estate listing comes up with certain characteristics (land use, known wetland polygon, etc.) in order to notify land conservancies and the like to be able to keep up with parcels for sale that may have habitat for endangered species.

Does anyone know if this is possible?

Thanks!

michelesharp · Answer

I’ve seen a few organizations set up workflows that are fairly close to what you’re describing. One option is to use the MLS feed in combination with parcel shapefiles and then run automated checks in ArcGIS or QGIS. If direct API access to Zillow or Redfin turns out to be limited, you could still rely on state or county-level open data portals that often publish parcel boundaries, zoning layers, and environmental overlays. Setting up a scheduled script that flags intersections between new listings and sensitive areas can help streamline notifications for land conservancies.

In Europe, this kind of approach is also gaining traction in coastal regions where environmental factors are critical for long-term planning. For instance, on platforms such as Living On The Cote d'Azur, which focus heavily on regional property insights, mapping layers can be an important tool for understanding both restrictions and opportunities. If you want to see how regional property data is often cross-referenced with location intelligence, you can click here for an example of how it’s applied in practice.

The key will be finding a consistent and reliable data source for listings, since once you have that, tying it into shapefiles for wetlands or habitat areas is mostly a matter of automation.

morganrh · Answer

Thanks Josh, I'll look into that!

jcarlson · Answer

Your best bet is to look through the respective companies' websites and see if they offer some kind of API access to their data. These sites all pull from central real estate listing systems, so you may also want to look around to see if there is a state-based real estate listing service you can access directly, rather than go through a middle-man.

Whether or not this kind of data access is available, as well as what format the output data is in, will dictate the methods available to you to perform the kind of cross-checking you have in mind.

One potential method:

* Get parcel data from whatever local authority has it.
* Intersect parcels with areas of interest (wetlands, etc)
* Export a list of parcel numbers from the intersection
* Check new listings against a separate list (maybe a CSV or TXT file) based on parcel numbers.

That way, even if the data provider does not have spatial outputs like parcel shapes, you'll still be able to reliably identify any new listings that fall within these zones.

Not knowing the specifics of how the output data will look, it's hard to give a more concrete example. But I think this is certainly possible. After all, Zillow and others get their data from somewhere, so the same  should be possible for you. Mind you, it may not be free...