It's hard to imagine the pre-Craigslist days. Can you even remember how you sold a slightly used bicycle or a stroller or a car? Nowadays you have some options when it comes to selling your old treasures online and if you haven't tried Adbirds yet, you need to give the site a test-drive. Adbirds is similar to Craigslist, but I'd say it's more safe, sophisticated and mommy-friendly. Sure, if you sell on Craigslist, you get in front of a lot of eyes instantly, but sometimes it's too many. Let’s say I’m trying to sell a baby stroller. By the time...