Thank you for your ideas,  hshontz.

Once you create an estimate, your inventory will not drop down since Estimate is a non-posting transaction. You'll want to create a Sales Receipt and enter the number of an item that you wanted to be reserved. 

Here's how:

1. Click the Plus (+) icon, then choose Sales Receipt.
2. Fill out the necessary information.
3. Under the PRODUCT/SERVICE column, choose the widget and the number to be reserved.
4. Enter a 0 amount on the rate.
5. Click Save and Close.

To check if the total number of inventory is deducted, click Sales then choose Product and Services.

Don't hesitate to post here again if you have other concerns. Have a good day!