Marketplace integration (Amazon, Faire, Joor, TikTok Shop), how?

Magento as the order-of-record, marketplace as a sales channel. Three integration patterns:

• Channel manager (Channel Advisor, Codisto, Akeneo, Sellbrite), PIM/feed-based. Master catalog lives in Magento (or in Akeneo PIM), channel manager syncs product feeds out + order feeds in. Best for >5 channels. Cost: ~$400, $2,500/mo. Pattern I default to at $5M+.
• Direct API integration per channel, for <3 high-value channels. Custom Magento module per channel: Amazon SP-API, TikTok Shop API, Faire API, Joor API. Cleaner and cheaper long-term but each channel is ~$8k, $25k of dev work.
• App-level apps, Magento Marketplace has Amazon connector, eBay connector, etc. Cheapest but lowest-quality for fashion (poor variant handling, no GTIN auto-population, no marketplace-specific category mapping).

Fashion-specific: Faire (wholesale to indie boutiques) and Joor (wholesale to retailers) are essential for any brand with B2B share >15%. Both have decent Magento connectors. Zalando and ASOS Marketplace matter for EU; Nordstrom Marketplace for US prestige.

Inventory of truth question: pick one. If Magento → push to channels. If a PIM (Akeneo, Pimcore) → push to both Magento and channels. Mixing creates the “why is the SKU oversold?” chaos most fashion brands hit at $5M+.