REAL ESTATE
Real Estate Tax Records
Property records, tax assessments, lien data, and ownership history across 932 US counties. Automated pipeline with monthly data refresh and change detection.
The challenge.
A proptech startup needed unified property tax data across 932 US counties, but each county has its own website with different layouts, search interfaces, and data formats. No standardized API exists, and many county sites use outdated technology with CAPTCHAs and session-based navigation.
The approach.
County Site Classification
Cataloged all 932 county assessor websites and classified them into 14 template groups based on their underlying software (Tyler Technologies, Aumentum, custom, etc.). Built specialized parsers for each template type.
Selenium-Based Extraction
Used Selenium with custom wait conditions for each county template to handle JavaScript-rendered content, multi-step search forms, and pagination patterns that vary by site.
Schema Normalization
Mapped 200+ different field names across counties into a unified schema with 42 standardized fields covering assessed value, market value, tax amount, exemptions, lien status, and ownership chain.
Change Detection & Alerts
Monthly pipeline compares new extractions against stored records, flagging ownership transfers, assessment changes, and new liens. Generates change reports for the client's analyst team.
Sample output.
{
"parcel_id": "07-23-301-015",
"owner_name": "Greenfield Holdings LLC",
"property_address": "1420 Oak Park Ave, Tinley Park, IL",
"assessed_value": 284500,
"annual_tax": 6812.40,
"last_transfer_date": "2023-06-14"
}The results.
Counties covered
Property records
Normalized fields
Coverage rate
Tech stack.
Ready to get your data?
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