Hi, I’d like to ask if it’s possible to create a multi-vendor marketplace with shopify (similar to vinted.com or etsy) where everyone sells their own products and get paid. No external apps needed, just templating user orders and public profile for their own products. Anyone did something similar before? Thanks 
You would absolutely need an app for this kind of project, and surely a massive one. Why? Because you need to manage and access backend data (sellers, sellers product collections etc.), there’s a lot of things that comes into play and there is no way this can be done in any reasonable way from the frontend.