Run a DTC brand on Shopify and Amazon at the same time and you already know the real tax isn't ad spend or fulfillment. It's reconciliation. Amazon Seller Central reports revenue, fees, and settlements on its own schedule and in its own format. Shopify reports orders, refunds, and processing fees in a completely different structure. Nothing lines up by default. That's the core problem this page is about: what ecommerce analytics for a brand selling Shopify and Amazon should actually look like once you stop accepting two logins as normal and start asking for one number you can trust.