Experify - Connecting you to owners of products for honest opinions.
Backflip - Selling your electronics just got easy
Whatnot - The safest place to buy & sell collectibles
Facebook Marketplace - Marketplace is a convenient destination on Facebook to discover, buy and sell items with people in your community.
Fobo - Forget Craigslist, use this to buy/sell electronics (SF)
Findy.com - Thousands of marketplaces, one interface.