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1. Click 'Vendors' tab on 'Supplies' page.
   
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   , Or
2. Click 'Add New' tab next to 'Vendor' field on 'Create Supply Type'/'Create Supplies' page
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3. Enter vendor name and details 
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4. Click 'Create'

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Create Locations

You can create a 'Location' e.g. a room, a cupboard, a drawer and link it with the supply. This will help you to track the actual storage location of the 'Supplies'. 

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