A few years ago when I just moved to my neighborhood, I got a paper mail from nextdoor. It's a welcome mail and has real people name on it. The mail says someth

A few years ago when I just moved to my neighborhood, I got a paper mail from nextdoor. It's a welcome mail and has real people name on it. The mail says something like "John Smith, your neighbor, would like to invite you to join our community". I had never heard of nextdoor before, so I thought it's from my own HOA because otherwise how would they know I'm new here. So I signed up and quickly realized I just fell for a "growth hack".