Where to sell used Backpacks?

I bought a couple travel backpacks for my family for a recent vacation. We're not going to need it anymore. Where would the best place/safest place to sell these online? Facebook marketplace is a big NO for me. I was almost scammed on there and don't want to relive that experience.

Trying to sell a Cotopaxi Allpa 42L and a Pakt Travel Backpack 35L