Hi
I'm a python/Django programmer who works with an Angular.js/bootstrap front end developer
From your description, you want to be able to upload csv files which have product data in them and then get no auctions, average price etc from ebay.
We can do this, but I am assuming you will sign up with ebay to give us access to the api.
We work on the basis, that stage 1, I make sure that we have understood all your needs
Stage 2, I create an RESTful backend API service. This allows interaction with the database via API calls.
Stage 3, we create an interface to work with the backend.
We work this way as it allow you to add new interfaces in the future, i,e mobile web, apps etc
Thanks
Marc Nealer