Odoo can manage multiple companies within the same database. This feature allows you to consolidate some of your system administration and manage more complex operations. As a rule, multiple-company configuration is an advanced topic. You should be very comfortable working with single-company configurations before you begin looking into multiple-company configurations. When managing operations, Odoo's warehouse management and analytic accounting abilities are often preferable to configuring multiple companies.
A good general rule is that if a company is not a separate legal entity, then it shouldn't be set up as part of multiple companies in Odoo. However, every business requirement is different, and the ability to use multiple companies in Odoo may allow you to easily implement a solution that otherwise may have been difficult.
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