Within FrontAccounting Inventory Locations are aimed at branch offices.
Purchasing You can create purchase orders against suppliers but you must assign the PO to a particular Inventory Location. The supplier is expecting to deliver to that location.
When you receive the items the Goods Received Note (GRN) will record which location you received the items into. You can split a PO into separate locations but you must enter a separate GRN for each location. The PO will stay outstanding until all items have been received.
Selling On the sales side FrontAccounting assumes you will deliver to each customer branch from a specified Inventory Location. This is specified as the default location on the branch.
When you enter a quotation FrontAccounting will assume the Inventory Location to use for the quotation is the one specified for the customer branch. If you do not have the 'Allow Negative Inventory' flag set then you will not be able to enter the quotation if there is insufficient inventory at the location for the branch to meet the needs of the quotation.
When a quotation is entered it will create a stock demand against the default inventory location for the branch. This can not be changed.
A sales order is the same as the quotation.
Delivering When you deliver to the customer you can change the 'deliver from ' location, but it is at the delivery order level. Individual items can not be delivered from different Inventory Locations.
Tips and Tricks
Consider setting the 'Allow Negative Inventory' flag (see Setup). This allows you to enter quotations when you do not have inventory, also you can do stock location movements prior to delivery of an order.