A marketplace is two apps in one. You have a buyer or customer experience and a provider or seller experience. Both need full onboarding, profile management, core workflows, and push notifications. Then you need a trust and safety layer connecting them: reviews, disputes, verification, and payments with splits.
The chicken-and-egg problem also shapes the build. Most marketplaces need supply before demand will come. That means the provider/seller side often needs to be built first and well, which shapes your Inception strategy.