Stocks are managed in detail mainly in Sage 300 either through purchase cycle or inventory adjustment; stocks can be divided location-wise and warehouse-wise. So, when Sage and WooCommerce are integrated, the stock should sync from Sage300 to WooCommerce according to the business requirement. WooCommerce can show a combined stock; if WooCommerce has location-wise stores, then it can store the location-wise inventory. But always Sage should maintain stock/inventory and that should sync to WooCommerce.