Marketplace Deal Checker

See if Facebook Marketplace listings are good deals based on recent eBay sold prices.

Detailed Description Stop overpaying on Facebook Marketplace. Marketplace Deal Checker shows you whether every listing is fairly priced by comparing it against real eBay sold data in real time. A small glass badge appears next to each price telling you if it's a great deal, fair price, or overpriced. HOW IT WORKS As you browse Facebook Marketplace, the extension automatically checks each listing against recent eBay sold prices. Two parallel searches run per item for accuracy, and statistical outlier removal ensures you get reliable fair market values. FEATURES Deal scoring: Great Deal, Good Deal, Fair Price, High, or Overpriced Fair market value shown for every item Savings or overpay amount calculated instantly Condition-aware: flags broken, for-parts, or damaged items so you don't get misled Click any badge to see the eBay sold listings yourself Adapts to Facebook's light and dark themes Supports collectibles at any price (trading cards, designer goods, watches, etc.) Skips vehicles and real estate where eBay comparisons don't apply No API key required, no account needed, completely free PRIVACY This extension only activates on Facebook Marketplace pages. It reads listing titles and prices to search eBay for comparable sold items. No personal data is collected, stored, or transmitted to any third party. All processing happens locally in your browser.