Hi there,
Since this is your first post in the Community, I'd like to give you a warm welcome!
I see you've spent a lot of time using the program. We appreciate your loyalty with QuickBooks. At this time, it's not possible to set up an item to hit 3 accounts unless you break that item down to 3 different items. Currently it's 1 Item to 1 GL account. I think this feature would be great feedback for our engineers. I encourage you to send this feedback to our engineers by clicking the Help menu and looking for Send Feedback Online.
In the meantime, don't hesitate to ask questions. I'm here to help. You can also contact our support team using this link here.