Guides.
How the data works, written by the people who build it. Each guide explains a source, what it contains, where it is reliable and where it is not, so you can decide what to buy before you talk to anyone.
- What is in a property record?
The fields in an assessor and recorder file, where each comes from, what is reliably filled and what is not, and how the parcel key joins them.
- How automated valuation models work.
How automated valuation models actually work: what an AVM is trained on, why accuracy varies by market, how to read a confidence score, what a commercial AVM can and cannot do, and how to test one before you license it.
- ZIP code demographic data: where it comes from.
The Census, HUD crosswalks, licensed consumer data and parcel-level property files compared for ZIP-level demographics, home values and rents, with the ZIP-versus-ZCTA problem explained.
- Real estate license data, explained.
What a regulator's license roster contains, how statuses and license types differ by state, why expirations cluster, and how monthly deltas become recruiting and compliance signals.
- Short-term rental data and aggregation, explained.
How short-term rental data aggregation works: what a listing row contains, how listings are deduplicated across Airbnb and Vrbo, how occupancy and revenue are estimated from calendars, and how a listing is traced to a parcel and owner.
- Insurance x-dates, and how they are derived.
What insurance x-dates are, why a home insurance policy renews on the purchase anniversary, how the recorded sale date becomes an x-date, what refinances do to confidence, and what an x-date data file contains.
- A guide to building permit data.
What a building permit record contains, why permit data is a county-by-county patchwork, which jurisdictions name the contractor, and how permit history becomes roof age and contractor rankings.
- How to verify a phone is a live mobile.
Line type, carrier and activity checks explained, why a portability database matters, how name-on-phone matching produces strict and wide cuts, and where DNC and litigator scrubs fit.
- Point-in-time data for backtesting.
What point-in-time integrity means, how look-ahead bias creeps into property and labor panels, why snapshots beat current-state tables, and how public-record panels are built for research.