Help with multiple formulas for inventory tracking

Hi all!

I've started making an excel sheet for my office that will track both our monthly sales and our inventory in one spot, instead of the multiple workbooks we have now.

My vision for it was to have all the installations we have scheduled be added to the January Sales sheet after each one is scheduled. Then to have them be sorted by install date after each addition, I've looked into a few different ways to have this be done automatically (such as using a macro) but was wondering what would be your best recommendation. We typically don't exceed over 100 lines on the sales sheet.

The inventory sheet is where I am having difficulty with the formulas. I am trying to come up with formulas that will show on what day we will run out of each item. So if I were to put the total inventory on hand that we have for 1/1/2022, I want it to use the sales sheet to calculate the total units we will have based on when they will be installed.

For example, I put that we have 20 Sani32K on 1/1/2022 and have one being installed 1/3/2022, so I am hoping the inventory sheet will show that on 1/3/2022 we will then have 19 units left, and we can update the total inventory we have each day so it can subtract from the correct number.

I hope the way I explained this makes sense. I can't figure out a formula that could do this for me and I think I'm over thinking things or trying to create something that just won't work.

Any help in the right direction would surely be appreciate!

Thank you!