eBay / Whatnot / Discord as secondary channels, how do they hook into Magento?

Magento as the order-of-record, secondary channels as additional sales surfaces. Pattern per channel:

• eBay, channel manager (Codisto, ChannelAdvisor, Sellbrite) or direct eBay API integration. Best for graded slabs and high-ticket sealed product where eBay’s auction format and global reach matter. Magento pushes listings + inventory; eBay pushes orders back into Magento for unified fulfilment. ~$200, $800/mo for the channel manager.
• Whatnot, live-stream auction platform exploding in TCG (sports cards especially). API integration is newer + lighter; most retailers run Whatnot as a separate inventory bucket with manual reconciliation post-stream. Magento exposes a “Whatnot allocated” stock-status to prevent oversells. Whatnot takes 8% + payment processing.
• Discord, community + community-only drops. Pattern: a Discord bot connects to a Magento custom endpoint, posts new singles + drop announcements in the #drops channel, and gates “Discord-only” product visibility behind a customer-group flag (members get the link, non-members see 404). Drives loyalty + repeat purchase, especially for Magic SCG-tier and Pokemon collector channels.

Inventory of truth: pick Magento. Push to channels. Mixing creates the “why is this Charizard oversold?” chaos most TCG retailers hit at $1M+.