Listing Price History Overlay

WHAT IT DOES

Listing Price History Overlay automatically scans real estate and property listing pages to uncover the complete pricing journey of any listed property. It detects and extracts original listing prices, every recorded price change, current asking prices, and listing duration, then presents this data as a clean visual overlay directly on the page. The overlay displays a mini-chart or timeline showing price movements over time, highlights price drops and increases, calculates percentage changes, and marks significant events. It updates dynamically when page content changes, ensuring you always see the most current pricing history without manual page refreshes.

WHERE IT RUNS

This extension works on major real estate platforms including Zillow, Redfin, Realtor.com, Trulia, and hundreds of property listing sites worldwide. It also supports regional and local MLS-based sites, classified property portals, and custom real estate CMS platforms. The overlay automatically activates on property detail pages and listing result pages where price history data is present. For sites without native price history support, the tool can still detect price patterns from page text, such as "price reduced," "price change," or date-stamped price mentions in the listing description.

HOW TO USE

Install the extension and navigate to any supported property listing page. The overlay will appear automatically if price history data is detected. Use the toggle button within the overlay to enable or disable the display at any time. Click the manual scan button to force a fresh scan if new price data loads or if the page updates via AJAX. The overlay includes a small drag handle for repositioning, and its position is remembered per site. For sites where automatic detection fails, use the per-site override feature in the extension settings to customize selectors or enable compatibility mode.

TECHNICAL SECTION — SELECTOR ENGINE AND HISTORY INFERENCE

Unlike other tools that rely solely on known CSS class names or hardcoded site-specific parsers, Listing Price History Overlay employs a multi-strategy selector inference engine. It first attempts to locate structured price history data using a curated database of site-specific selectors that is updated regularly. If no match is found, it falls back to a heuristic scanner that identifies price patterns in the DOM by looking for currency symbols, numeric values, and contextual keywords like "original," "current," "reduced from," or "was." It then correlates these values with timestamps by scanning for adjacent date elements, relative time markers (e.g., "2 weeks ago"), or listing duration indicators. The engine also monitors DOM mutation events to detect AJAX-loaded content, re-scanning only the mutated subtree to preserve performance. All detected price points are sorted chronologically, normalized to a common currency format, and rendered as a line chart with threshold markers for significant changes (e.g., >5% drop). This dual approach ensures high accuracy across thousands of sites while maintaining adaptability without per-site custom code.

THE PANEL — DRAG / PER-SITE POSITION / SNAP / COLLAPSE / RESIZE / ESCAPE

The overlay panel is fully interactive and user-friendly. Drag it anywhere on the screen using the handle at the top of the panel; the position is saved per site so it stays where you left it. The panel includes a snap-to-edge feature that gently anchors the overlay to the nearest screen edge when released. Click the collapse button to minimize the panel to a compact pill showing only the current price and a small indicator; expand it again with a single click. Resize the panel vertically by dragging the bottom-right corner to view more or fewer data points in the chart. Press the Escape key at any time to instantly close the overlay; it reappears on the next page navigation or refresh.

PLEASE NOTE

This extension requires the free BotGentz companion extension to function, as it provides the underlying content script injection and cross-origin communication framework. Real estate websites frequently update their layouts and class structures; price history detection may break temporarily after such updates. The extension includes an automatic update check and will prompt you when script updates are available. No personal data, browsing history, or property data is stored, transmitted, or shared. All price history extraction occurs entirely locally in your browser; no information is sent to any external server. The extension does not access or store login credentials, financial data, or personally identifiable information.