Hi! I would like to share my experience. In our work we also take into account the wishes of the client. Moreover, before we start, our programmers choose the optimal vector of development: Open Source, SaaS or White-Label. In fact, the choice of the optimal solution is one of the important tasks when creating a marketplace.
We also create important functions in applications: the ability to choose a payment method and the one-click checkout function.
Therefore, in order to learn more about this topic, theory and practical cases help in learning how to create a marketplace
https://celadonsoft.com/best-practices/5-marketplace-problems-faced-by-online-business-and-their-solutions