You can’t just use Memberstack to achieve this. Two sided Marketplaces has been done on Webflow, e.g. Unicorn Factory made by Connor Finlayson. There is a video where he talks about briefly on how to get started, using a combination of Webflow, Memberstack, Airtable & Zapier.
This should be a self-hosted project. I would recommend Coffee Cup’s site designer, Pinegrow or Wappler. These are desktop applications designed for advanced designers building multi-level processes for a front end user. The back end is where you will build all of those variables. A hosted software won’t accomplish this. Check these three out, you’ll see what I mean after reviewing the feature list. You’ll need a number of databases to manage user levels, etc. Wappler will be the most flexible because you can build and connect directly inside the app.