I don't have an answer for your question, as those sites come and go due to being abused. Someone else here may know of one, but I would not add business depen

I don't have an answer for your question, as those sites come and go due to being abused. Someone else here may know of one, but I would not add business dependencies on it. Craigslist have teams dedicated to handling abuse. An alternate method would be to have a forum that lets users send private messages each other so they don't even have to expose any email trails at all. A forum also gives you a place to quickly reach out to your most engaged users for announcements.