in my opinion there should be an option to add the expense incurred in the Inventory Transfer form itself. many business operate from different location under a single VAT registration. in our country they are just classified as different place of business. also, it is true that the business will incur a minimum expense for transportation when transferring inventory from one location to another. in this case the inventory listed in Manager remains the same while the inventory location changes along with the average cost of the inventory taking into consideration the expense incurred for inventory transfer.
Edit: Similar to Production Orders : transfer