Operating on-line marketplaces for sellers and buyers of goods and/or services; Provision of an on-line marketplace for buyers and sellers of used consumer electronics, consisting of phones, smartphones, tablets, laptops, video games, video game consoles, video game handheld devices, home tech, watches, wearables, virtual reality systems, voice assistants, thermostats, speakers, and vacuums; operating online marketplaces for sellers and buyers of goods and services; online trading services in which sellers post products or services to be offered for sale, and purchasing is done via the Internet in order to facilitate the sale of goods and services by others via a computer network; providing evaluative feedback and ratings of sellers' goods and services; providing a searchable online advertising guide featuring the goods and services of online sellers; providing a searchable online evaluation database for buyers and sellers; advertising and advertisement services