Type error upon product import

Hello there, moonshot.

Yes, we can import inventory item in QuickBooks Online. There's a possibility that these inventory items are already in QuickBooks Online. Hence, the system is not allowing you to import them again.

Instead, you can create quantity adjustments to the inventory items so you can add up the remaining quantities. Here's an article that you can use for reference: Adjust inventory quantity on hand in QuickBooks Online.

You can also browse this link item types and how to manage them: Change product and service item types in QuickBooks Online.

Aside from that, it's best to consult your accountant before create those adjustments. They know what's the best way in handling your books.

Feel free to drop by if you need anything else. Have a great day!

So you’re saying there’s no way, apart from interacting with the API, to update the inventory quantities of 163 items at once? Not sure if I have time to do drop down menus 163 times.

I appreciate your time getting back here, moonshot.

I'll share the steps on how you can adjust the inventory quantity at once.

Here's how:

1. Go to the Gear > Products and Services.
2. Click the funnel icon and select Inventory from the Type drop-down menu.
3. Select Apply.
4. Put a check mark on the box before the Name column to select all inventory you want to adjust.
5. Click the Batch actions drop-down list and select Adjust quantity. It will open the Inventory Quantity Adjustment page. 
6. Change new quantity as needed. Optional: The default inventory adjustment account in QuickBooks Online is Inventory Shrinkage account. You can use this account or create a new account if needed to track it separately.
7. Save and close.

I've got these sample screenshots for a visual guide:

Once done, you can run the Inventory Valuation Detail report. This will display the quantity on hand, value, and average cost for each inventory item.

1. On the left panel, click Reports. 
2. Type Inventory Valuation Detail in the search field.
3. Select the Report period, and click Run report.

Please let me know in the comments below if you have further concerns with QuickBooks. I'm always here to help out. Take care and stay safe.