Property Tax Lookup

Type in any US street address and get that property's tax and appraisal record, pulled live from the county's own website.

What it was

There is no national property-tax API; every county runs its own appraisal site. This app worked out which county an address was in, found that county's appraisal site, opened it in a headless browser, and had an LLM read the page and pull out structured data such as owner, assessed value and tax amounts.

Once it learned how a county's site worked, it remembered the URL and scraping pattern, so later lookups in the same county skipped the discovery steps. Results were cached so repeat lookups were instant.

How it worked

• Four-step background pipeline (normalize address → identify county → find county website → scrape and extract); the page polled each step's progress every second.
• County lookup from ZIP code; county-site discovery with Tavily web search plus an LLM picking the right result.
• Playwright for scraping; DeepSeek through OpenRouter to turn raw HTML into JSON.
• Every step saved to SQLite as it finished, so partial progress was always visible.

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