Only sell stuff that's YOURS. That toy you've outgrown? Perfect - give it a new home and pocket the cash. Your brother's stuff? No way! Selling things that aren't yours = instant ban. Ouch.
Everly checks every listing first - it pops up on the site once she gives it the thumbs up.
Then get it to her: Sunday meetup, letterbox swap, or email her your own plan. Easy.