How does WP-Lister manage FBA inventory?
First of all, if you use Fulfillment By Amazon (FBA) for any of your items, you need to enable FBA support on the general options page.
The FBA Inventory Report
With FBA support enabled, WP-Lister will automatically request and process an FBA Inventory Report once per day. This is important because it is the only way for WP-Lister to know your current FBA stock levels - and which items are set to use FBA.
When you send new stock to FBA, WP-Lister will update the FBA quantity automatically within 24 hours after your shipment was processed by Amazon. For FBA-only items there is nothing else to do - for items with FBA and non-FBA stock please see the notes below.
You can request a fresh FBA inventory report manually at any time - just visit the Reports page and click the Request Report button on the bottom. Select FBA Amazon Fulfilled Inventory Report and click Submit Request. Your report will be processed automatically once it has been generated.
It is also highly recommended to request and process an FBA Inventory Report after importing your products from Amazon. Products can only be imported from a Merchant Inventory Report - but unfortunately, that report will only show an empty quantity column for FBA enabled items. So your imported products and listings will show as out of stock - until an FBA Inventory Report is processed.
Please note that once you use FBA for a particular SKU, it will always show in your FBA Inventory Report until that SKU is removed from seller central. When the stock level reaches zero, it will still have FBA enabled - on Amazon as well as in WP-Lister. However, you can let WP-Lister use remaining stock from WooCommerce (as seller fulfilled) using the fall back to seller fulfilled option:
WooCommerce stock levels and the Fallback Option
The WooCommerce stock level is supposed to equal the total quantity of FBA and seller fulfilled units combined. So if you have 10 units on FBA and 5 more units in your local store, then WooCommerce should show 15 units in total.
As long as there is stock in FBA, WP-Lister will list the item as FBA fulfilled. When there is no more stock available in FBA, but still remaining stock in WooCommerce, it can switch to Seller Fulfilled - if you enable the "fall back to seller fullfilled" option in the FBA settings.
In the above example, after selling 10 units via FBA, the stock in WooCommerce would be down to 5 units. With the "fall back to seller fullfilled" option enabled, WP-Lister would treat this product as Seller Fulfilled now, and tell Amazon that you still have 5 units at your local store. With fallback disabled, the remaining 5 units could only be purchased in WooCommerce.
How the WooCommerce stock level is updated
When processing an FBA Inventory Report, WP-Lister will update the stock level in WooCommerce as well - but only if the current stock level in WooCommerce is lower than the FBA stock level.
This makes the process of adding new FBA stock very simple - as long as your FBA enabled items are only available via FBA.
If you keep local stock in addition to FBA stock - as in the example above - there might be one extra step required when you send new stock to FBA, which is updating the stock level in WooCommerce to reflect the total quantity of your local stock and all FBA units.
Let's assume your FBA stock level is 0 and you ship 10 units to FBA while having 5 units remaining in your local store - then the quantity in WooCommerce needs to be 15. If you sent the 10 units from your local store it should already be 15- but if you get new products and ship them to Amazon right away without adding the inventory to your local store, you need to make sure to increase the stock level in WooCommerce accordingly.)