- Retail POS for Mac or PC
- Navigate to Catalog > Products
- Click Export List...
- Select CSV format
- Your product list will now download into a file called product-list.csv
- Open the file
- Remove all of the columns from the file except for handle, sku, supply price, and [the inventory column for the source outlet]
- Rename the inventory column to 'quantity'
- Upload the file into a stock transfer
- Process the stock transfer