Inconsistent/varying inventory

Also is there a way I can record which jewelry item each purchase was for ? Like a note "14k Gold braided 20" necklace"

Hello there, @fatweasel.

You can enable the inventory tracking feature then add each products you purchase. From here, you can associate it under Inventory Asset account. I can guide you on how to do it.

First, you can follow the steps below on how to enable the inventory tracking feature:

1. Go to the Settings ⚙
2. Choose Account and Settings.
3. Select Sales.
4. Click the Edit ✎ link in the Products and services section.
5. Enable the Show Product/Service column on sales forms.
6. Turn on both Track quantity and price/rate and Track inventory quantity on hand.
7. Click Save and then Done. 

Now, you can add the product items you're purchasing. Just make sure to indicate its selling price and its cost.

Once you've added your products, you can now start writing a check, an expense transaction or a bill to track your purchases.

By doing these, you'd be able to generate the Inventory Value Summary report. It displays  a list of each inventory item, and how they affect quantity on hand, value, and cost.

I'm adding these articles to help you manage your inventory items:

• Set up and track your inventory in QuickBooks Online 
• Reorder inventory or supplies from vendors 
• What is the difference between bills, checks, and expenses? 

Feel free to leave a comment below if you have other questions or concerns. I'm just a few clicks away.

@fatweasel 

You may need an additional app to manage matrix inventory.

I added some products following your guidelines but when I go to write a check, I dont have the same options as you. I can only "Category" and I dont have "Item details" like you do so there is no option for me to select a specific inventory item that I am purchasing?

Ok so I think I have it figured out, I had to enable Item Details in Settings.

To be sure I'm doing this correctly; when using this method and I write a check to purchase an item I have already added in my Products will I Categorize that check as an "Inventory Asset", or "Cost of Goods Sold"?

Don't sweat it, @fatweasel. I'm here to help you enter your inventory items right away.

All you need to do is turn on the Show Items table on the expense and purchase forms option from the setting. It only takes a few steps. 

Here's how:

1. Go to the Accounts and Settings.
2. Select the Expenses tab.
3. In the Bills and Expenses section, turn on the Show Items table on the expense and purchase forms option.
   
4. Click Save and Done.

These instructions are also available from our guide on how to use Inventory Items on Bills.

I'm also adding this article to learn how QuickBooks handles inventory assets, average cost, and Cost of Goods Sold (COGS): Understand inventory assets and cost of goods sold tracking.

Should you need further assistance with inventory tracking, please let me know. I'm always around to help. Have a good one.