[eastbayjake]

If you're building a marketplace, your SaaS offerings are more limited because the functionality diverges from B2C Retail... as you've probably (re)discovered, content moderation and approval for catalog information from your third-party sellers is crucial[0] and you'll need to solve interesting problems in promoting and suppressing search results when the business asks you to support paid partnerships with some third-party sellers as "official resellers" or sponsored listings.

Right now Mirakl is the big incumbent in marketplace APIs, but whether that's the right answer will depend on your company's scale, technical capabilities, and margins.

[0] I keep a folder of examples of unmoderated third-party seller content embarrassing large companies running marketplaces, this one is my go-to example: https://www.independent.co.uk/news/world/americas/ashli-babb...