Custom Wordpress plugn

Flatrock Technology Group is looking for a custom Wordpress e-commerce Plugin that functions similar to a reverse-auction plugin that can be installed onto most Wordpress themes and work seamlessly with Visual Composer plugin by CodeCanyon, for our client who is a broker of building supplies. Below is a rough outline and description of what is needed. Basic functions: We would like to manually create user accounts for this plugin versus allowing users to have the ability to sign up. Users will be in one of 4 groups: Admin, Broker, Supplier, and Buyer. This plugin as a whole should be built with a drag and drop backend interface, in which logins, drop downs, etc. can be placed into a specific area on different pages for ample frontend functionality by all users. The main function of this plugin is to automatically match order requests from the buyer with offerings previously input by the suppliers. The buyer creates an order request, and if any supplier provides all of the items in the request that meet the criteria input by the buyer, then a match is made. Once a match is made, a notification must be sent to both the buyer and the supplier for them to agree upon electronically through a link that is received via email (again, this email is auto-generated by the plugin application). Once both the buyer and the supplier agree to the matched order a notification (via auto-generated email) is sent to the broker, and an invoice is created and sent to the buyer. If no match is made ALL suppliers are notified and are able to view the unmatched order requests to see if they wish to fill that order. User Group Details: Admin: These users have the ability to manage the application and all of its data. Create/Delete users, create /edit products, edit order requests, invoices, etc. Broker: These users will be able to see and edit supplier, order requests, matched order details, and invoices. These users will also need to be able to create and download data and reports from the plugin in .CSV format. Supplier: These user accounts will need to be able to input their product offerings from a pre-selected list of products. They will also need to be able to change pricing on a regular basis, and will need to be notified if the price data becomes older than 7 days. Cannot see other suppliers pricing. Can view all unmatched orders. These users also need to view/sort all of their matched orders (matched, shipped, completed etc.). Buyers: These user accounts will be able to create order requests by selecting product items from a pre-defined list of products. Once the order is matched to a supplier, including shipping methods and deliver-by dates, receives notification, and must agree to terms to continue. These users need to be able to view/sort all of their own orders (unmatched, matched, shipped, completed etc.)