Creation of a Multi-Vendor Online Store on Python + Django

Hello!
We are looking for a specialist who can create a multi-vendor marketplace/online store like
3dsky.org, cgmood.com or greatcatalog.net. In the future, there will also be a need to develop websites for servicing a Network of Pharmacies (at least one pharmacy) in one of the Eastern countries of the European Union, a large Restaurant in the EU or Ukraine and a Home for Orphans in Ukraine, as well as technical support and improvement of these websites - therefore, it is extremely important for us to choose and collaborate with a competent performer with whom we could work on a permanent basis.
 
The work involves: creating Frontend (based on the provided design, which is in the refinement stage), Back-end on Python + framework Django (this is at our discretion, there may be other, more effective stacks).

The site will interact with more than hundreds of thousands of digital goods/models, the minimum size of one is 50 mb, so it is important for the performer to understand things like API, database, servers for storing this content, implementation of Payment Systems for distributing commercial profits between the platform and the authors of the models: commission for the online store/platform and royalties for the model owners, the ability to withdraw these funds and other tools to fully implement the functionality, similar to the functionality implemented on the aforementioned sites 3dsky.org, cgmood.com, greatcatalog.net. Please note the following clarification: we are talking about functionality! Advertising sections, informational sections are not taken into account! This will not be present at the initial stage, these branches will be added later.  
Our marketplace will be simpler than the provided examples, in the sense that unnecessary informational sections will not be included at the initial stage, and the most important functions for us are filtering products by format, brands, style, color, materials and categories, searchability by keywords in the search field, automatic distribution of commission  from sold goods for the author and the platform - that is, just like in the provided examples at their core.

 The price may vary, but at the initial stage, it is important to adhere to the specified cost. We can agree in advance on additional compensation in case of successful work or testing of the marketplace with a large number of models. In the conditions of positive commercial dynamics of the project - we will consider the performer as a permanent technical or other type of worker.
 Thank you for your attention!