Re: Invoicing my customers for inventory items is not decreasing my inventory and increasing my C...
You and I are covering your Error in depth in the other topic, where I explain you are using Inventory Item incorrectly and everything you described is Noninventory. Your initial setup of Expenses tab was wrong for providing Job reporting data; your change to Inventory also was not the Right Item Type to use.
Please see the other topic you asked and I answered, and let's keep to that, since that is already there:
You use two sided Noninventory Items; leave the Cost and Rate (price) as 0. When you enter this into an actual purchase entry, you job track it as Billable to that job. When you do this, then using the Add Time & Costs, function, your Cost appears as the customer's Price.
Never use JE in QB for this. Not for Job tracking, not for Anything with names, not for AP, AR, no items can be listed here, not for Sales, Sales taxes, etc.
"For example, we buy a 1000ft spool of MC Cable for a specific job, but say we only use 900ft, then how would I add that left over 100ft to inventory to be used on a later job without making a JE?"
Only you know if that is inventory or not, based on the details I went into on your other topic. You seem to be treating Material as if that is Inventory. Products that are Specifically Names, are inventory. And Yes, you need to open the original Purchase and Split the entry into two lines:
Noninventory item "Materials" $900 job tracked for Smith
Same Noninventory item "materials $100 job track to Jones, or not Job Tracked at all.
That's why you have Multiple entry lines on purchase transactions.
And if you want to handle this as Period Inventory, I covered that in the other topic. Example:
You realize at Year end that the Not Job Tracked $100 still is on the shelf. You analyze all materials on hand and determine that $50,000 of Stuff posted into COGS from Purchases, still is on hand. You make One JE:
Debit Other Current Asset for "materials on hand" $50,000
Credit COGS for $50,000
Periodic Inventory = Rebalancing between those two, to reflect what still Is on hand and what is no longer on hand.