Chronicles of Data Collection… A Gargantuan Task

We get a lot of questions about the origination of our data on individual homes. The simple answer is that it comes from individual localities (mostly counties), which collect home facts, tax information and transactions as public data. But considering there are more than 3,000 U.S. counties, and many use vastly different systems to keep track of property records, you can imagine what a monstrous and complicated task even attempting this can be.

First, to collect and continually update the data, someone has to actually collect this data individually from each locality. Some counties require that people physically visit the county recorder’s and assessor’s offices to obtain property records and tax information, some counties have images of deed documents online that have to be re-keyed into a database, and still other counties (the minority) have complete records already online that are available for download. The latter group is obviously much preferred.

Second, the data from each specific county has to be standardized into one format (probably the most difficult and laborious part of the process). Very seldom can you find several counties using the exact same system to track their property records (but we wish they did). The names and functions of offices keeping track of property records vary from state to state as well as, to a smaller degree, between counties within individual states. For example, in some states such as Connecticut, individual townships rather than counties oversee property tax assessments.

Our third step is to make sure we regularly update all this data as it appears on our site, which is currently on a near-weekly basis. (As a beta site, we are working to make these updates more regular. Our goal is to eventually update home values and data daily!) We also work to align this data with our satellite and street maps and where available, chart out individual parcels on the maps as well as sync with Bird’s Eye Views.

We currently have data on more than 65 million homes, or about 65 percent of the homes that exist in the U.S. As a beta site that’s been around just since February, we think this is pretty good, but acknowledge we have an enormous way to go in terms of finding new homes, updating data and in some areas, finding better data. We’re also working on ways to allow you, our users, to correct or add to data on homes you own. Stay tuned
for more on the topic of data collection…