This project posts videos on Douyin to attract traffic, then funnels viewers into private-domain communities for chat and promotion. Once enough trust and a follower base are built, leveraging the private domain, you buy used phones at low prices from Xianyu-like platforms and resell higher. This buy-low-sell-high model makes a single daily order very profitable. Thanks to the private domain, earnings are uncapped—as long as you keep stable traffic and fan interaction, you keep earning high profit. The model has big profit room and is relatively flexible, adjusting to market demand and supply—a very attractive startup project.