Facebook Marketplace
Local listings, plus automated offers on the ones that clear your margin.
Filtrs.co searches Facebook Marketplace listings in your area and ranks them by estimated margin.
Automated offers
With the paired Chrome extension, Filtrs.co can send a polite offer on listings that clear your margin threshold, at a discount you set. It runs inside your own logged-in browser, never sees your Facebook login, and starts in testing mode so nothing is sent until you switch it on.