Map the structure before any data moves. Each Shopify store usually belongs to one Odoo company, and each Shopify location to one Odoo warehouse. Shopify order names such as #1001 are not unique across stores, so the integration keys orders on the Shopify order ID and the store.
Odoo shares new products and contacts across companies by default, while product cost is company-specific. Decide whether companies share one catalog, and restrict records with the Company field where they should not. On a Standard plan, turning on multi-company moves the database to Odoo’s Custom plan.
For stock, choose which warehouses feed each Shopify location and what buffer to hold back for fast sellers. If one store sells stock owned by another company, Odoo’s inter-company transactions can create the counterpart orders and bills.