Defining Warehouses 
If your company stores items, you need to define the storage locations as warehouses.
The standard warehouse stored in the system is used as a basis for all transactions.
You can define any number of warehouses, depending on how you manage your inventory. In most cases, a distinction is made between several warehouses. These can be physically separate facilities, located at different sites.
A warehouse is defined independently of the items stored in it. All of the items can be stored in all of the warehouses, or one item can be stored in just one warehouse.
It is important to know which items and their quantities are stored in each warehouse in order to optimize inventory and provide a more transparent overview of inventory.
Goods receipts in a warehouse from purchase documents and goods issues from a warehouse for sales documents must be known. Physical inventories are organized for each individual warehouse. If items are moved from one warehouse to another, these movements must also be recorded in the system.
Using SAP Business One, you can track all of this data in detail. Goods movements to the warehouse, within the warehouse, and from the warehouse are, therefore, specified for the storage location(s) concerned.
Procedure
In the SAP Business One Main Menu, choose
Inventory 
Item Master Data Inventory Data 
tab.Define the following for each storage location:
Identification key (warehouse code)
Name of the warehouse
Accounts for inventory postings, cost of goods manufactured, and allocation costs.
NoteThese columns are displayed only if the company manages an perpetual inventory system.
End of the note.When you have specified the data for a warehouse, choose Update.
The cursor then moves to a new row and you can enter another new warehouse by choosing the Choose From List icon, then in the List of Warehouses window, choose the New button. In the Warehouses - Setup window, you can define one or more new warehouses.
To set a warehouses as the default warehouse, select it and choose the Set Default Whse button at the bottom right of the tab in the Item Master Data window.
This warehouse is then always proposed automatically by the system, but you can specify a different warehouse for a particular transaction.
NoteWarehouse 01 has already been defined as the default warehouse in the standard system. If your company only has one warehouse, this means that you can enter all of your business transactions directly in the system.
Warehouse inventory is managed on a value basis in the balance sheet account. The appropriate entries are posted to the COGM account when a delivery is created for a purchase order. The account for the allocation costs shows the sales costs.
End of the note.