Hi,
First of all you have to enable the multi company feature from the settings, go to settings-> general settings, then click on "manage multi companies".
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After enabling this feature, open the company form and create the needed companies .Go to Settings -> Users -> Companies,
Suppose let there be 3 companies,
* Your company
* Company1
* Company2.
Company 1 is set as the parent company of the company2.
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This is how the parent and child companies are created and set.
Now we have to create users for this companies, go to Settings -> Users -> Users,
let there be three users,
* Administrator
* User 1
* User 2
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For the user 1 . current company is set as Company 1 and in the allowed companies, company 1 and company 2 is also given as the company1 is parent of company2.
User 2...
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Administrator...
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Now we have to configure Chart of accounts for each company, for that go to Accounting -> Configuration -> Settings,
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From here select company one by one and assign a chart of account and click the apply button.
Now we have to enable the multi Warehouse Feature,
For that go to Inventory -> Configuration -> Settings ,
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Now go to users form view and make the user1 and user2 as manager in inventory. Then login to users account and navigate Inventory-> Configuration -> Warehouse Mangement -> Warehouse,
Now you can see the warehouse in the company name created or you can create a new warehouse for the company.
Thanks