Hi there, @MatthewAccenttMarble. I'm stepping into the thread to share with you some insights about updating item prices in QuickBooks Desktop (QBDT).

Aside from modifying the prices  of an existing item via the Add/Edit Multiple List Entries or by opening each item manually, you can also use the IIF file to move your updated item list to QuickBooks. 

1.  Prepare your file.
2. Back up your company file before you import IIF files. This way, you can use your backup to restore your data if you ever run into problems.
3. Sign in to your company file as an admin. If you’re in Multi-user mode, go to the File menu, then select Switch to Single-user Mode.
4. Go to the File menu, then select Utilities.
5. Click on Import, then select Import IIF.
6. Select the IIF file you want to import, then select Open.
7. Hit OK to confirm the import.

You can review this article for more information: Export, import, and edit IIF files.

For more hints while working with your inventory items in the future, you can also check out the resources from these links:

• Set up Advanced Inventory
• Turn on Advanced Inventory

Let me know if you have any other questions while updating items' prices in QBDT. I'm just a post away to help. Keep safe!