Hi, I've built e-commerce apps as well as worked on features in marketplaces.

If you wish start from scratch and are looking to build an MVP (minimum viable product), I would strongly suggest building it in Ruby on Rails. The application can be developed very quickly. Most of the time gets spent in non-code related tasks including figuring out the features that you are looking for, understanding how your users like the features and what they expect, understanding if you users will need the features and the application that you are offering. Market research and UX exercises will help answer these questions.

Once there is a roadmap, the coding part is not that complicated. If you would like to know more, feel free to get in touch. :)