Property Tax Estimator Injector

WHAT IT DOES

Property Tax Estimator Injector scans real estate listing pages for property prices and location data, then calculates and displays estimated annual property taxes directly next to the listed price. A small badge appears beside the property price showing the estimated annual tax amount and the effective tax rate used for the calculation. Clicking the badge opens a floating panel with a detailed tax breakdown, including the property value, tax rate, annual tax, and monthly tax estimate. The script uses a comprehensive lookup table of average property tax rates by state, but also allows manual override of the tax rate and location. This gives homebuyers and investors an immediate sense of the true cost of ownership beyond the listing price.

WHERE IT RUNS

This script operates as a userscript within the BotGentz extension on any webpage that contains real estate listings, including Zillow, Realtor.com, Redfin, Trulia, and other property sites. It functions on any modern browser that supports the BotGentz extension, including Chrome, Firefox, Edge, Safari, and Opera. The script runs entirely client-side, processing all calculations locally without sending any information to external servers.

HOW TO USE

After installation, the script automatically scans the page for property prices and location data. When a price is detected, a tax badge appears next to it showing the estimated annual tax. Hover over the badge to see a tooltip with the location and rate used. Click the badge to open a detailed tax breakdown panel. Open the main panel to customize your default state, choose between average, exact, or custom tax rates, toggle the tax badge display, set badge position (left or right of price), or enable auto-detection of location from the page. Click "Scan Page Now" to manually re-scan the page.

THE MECHANISM THAT MAKES IT WORK

The script uses a multi-stage detection pipeline. First, it scans the page for property prices using a combination of regex patterns (e.g., "$350,000") and DOM selectors targeting price elements. Second, it detects location by extracting state abbreviations and full state names from address elements and page text. The script then looks up the property tax rate from an internal state-rate lookup table compiled from national average data. If the calculation method is set to "custom," it uses the user-defined rate instead. The tax badge is injected adjacent to the price element using DOM insertion, with position controlled by user preference. The detailed panel calculates annual and monthly tax amounts and presents them in a clean breakdown. The auto-detection feature allows the script to work across different real estate sites without requiring site-specific configuration.

THE PANEL

The script panel is built using BotGentz's BGPanel framework and provides comprehensive control over the estimator's behavior. The panel opens as a floating overlay that can be dragged anywhere on your screen, with a clean dark theme matching the tool's aesthetic. It includes dropdown menus for calculation method (average state rate, exact state rate, or custom rate), default state selection, and badge position (left or right of price). A text input allows you to set a custom tax rate percentage. Toggle switches enable or disable the estimator, show or hide the tax badge, and enable auto-detection of location from the page. Action buttons allow you to save settings or reset all settings to defaults. The panel collapses to a small icon when not in use and expands when clicked, remaining accessible but unobtrusive. Press the Escape key at any time to close the panel.

PLEASE NOTE

This script requires the free BotGentz extension to be installed and activated in your browser. The extension is available from the official BotGentz website. The tax rates used are state averages and may not reflect exact rates for specific counties, cities, or school districts. Actual property taxes can vary significantly based on local assessments, exemptions, and special levies. The script provides estimates only and should not be used as a substitute for professional tax advice. The auto-detection feature may not work on all sites; you can manually set the state and rate in the panel. All calculations and settings are processed locally and not shared with any third-party services. The badge may not appear if the page uses dynamic content loading; use the "Scan Page Now" button or wait for the automatic refresh interval.