aliyevrabbi/ebay-price-daemon

eBay Price Deviation Daemon is a small background program that watches eBay's Buy It Now listings for products you tell it to track, and alerts you when it finds a genuinely good deal. It runs continuously, scanning the search results for each product you configure, and sends a message to a webhook you set up whenever a listing's total price, including shipping, drops far enough below what you have told it the item is normally worth. What makes the alerting logic careful is that it checks two conditions at once, not just one. A listing has to clear a minimum percentage discount compared to the market value you set, and it has to represent a minimum dollar amount of actual margin. This stops the tool from getting excited about a cheap item that is a big percentage off but only worth a few dollars, while still catching a more expensive item that is a smaller percentage off but a large real discount. You configure everything through a single config file listing the products to watch, required and excluded keywords for each one so it does not match unrelated listings, your market value estimate, and your alert thresholds. It scans eBay's public search pages through a proxy service you provide, rather than trying to bypass eBay's own bot protections directly, and the README asks that you keep your scan frequency reasonable and follow eBay's and your proxy provider's terms of use. It is written in Python as a single main script plus a config file, with a systemd service file included so it can be installed and run continuously on a Linux server. The tool is aware that eBay periodically changes the layout of its search results pages, and it tries to detect and handle two known layouts, logging clearly when it fails to parse results so you know the page structure has changed again.