Xianyu

Xianyu is Alibaba's secondhand marketplace and the largest resale platform in China, covering everything from electronics and clothing to furniture and unused gift cards.

It sits on the Alipay payment and identity system, so escrow, dispute handling and seller identity verification come built in — the infrastructure that makes peer-to-peer resale workable at scale.

It is also used for local pickup transactions and for services and rentals, which pushes it somewhat past a pure goods marketplace.