CONTEXT
The whole system consists of four different types of users:
Buyers: Buyers are renewable power Manufacturer app users. Buyers may have several mobile devices that are using renewable power Manufacturer app. Each Buyer downloads and installs the renewable power Manufacturer app on their mobile device.
Sellers: People or organizations that own any form of renewable power generator like solar panels or windmills. A Seller can have multiple Generators. These users sign up through a Web Application
Installers: Installers recruit Sellers to become a participating seller in renewable power Manufacturer. Installers receive a commission on every transaction that the Seller is involved in. A Seller can have an Installer referenced while they are signing up. If there are no Installer mentioned no commission is paid.
GreenCoders: GreenCoders recruit buyers into renewable power Manufacturer. GreenCoders receive a commission on every transaction that the Buyer is involved in. A Buyer may or may not have a GreenCoder referenced. In that case no commission is paid.