It sounds like you’ve already put significant effort into making the quantity updates, especially given the size of your inventory, and I understand that option 2 may not be suitable for your needs, justin00195.
You can overwrite the quantity and costs of your inventory lists with an .IIF file. To ensure that it will be successfully imported, I recommend downloading our tool kit and using it as a reference in properly formatting the file. Take note that if your IIF file came from a third-party app, you'll have to contact the app’s technical support for further assistance.
Just a heads up, QuickBooks doesn't support directly uploading an inventory adjustment transaction type using an IIF file. You can use a third-party app to import the adjustments. Visit the QuickBooks Desktop (QBDT) App store and search for importing an IIF file to explore available options.
Please let us know if you have any additional questions or concerns.
