Resellers who list the same item on eBay, Poshmark, Mercari etc. by hand have one recurring nightmare: it sells on one site, they forget to end the others, it sells twice, and they have to cancel (which hurts their seller rating). Crosslisting tools solve this but cost $15–$99/month and want to log into your accounts. I wanted the cheapest possible safety net: - forward only your sale emails (one Gmail filter) - get a phone + desktop alert with the bin and one-click links to end the other listings - sold-twice warnings, ship-by reminders, sales & profit Stack: Chrome/Firefox extension, Cloudflare Workers + D1, Web Push for the phone app (no App Store needed), Stripe as merchant of record. English and Spanish. https://soldelsewhere.com/c/sideproject Feedback on the landing page and onboarding especially welcome.   submitted by   /u/x_scherer [link]   [comments]