Hello David, and thank you for choosing JUSTANSWER.com
YOu can use formulas/functions to pull data from specific cells, and populate OTHER cells.
However, the way Excel was designed, and HOW you are trying to use it....dont match up so well.
Formulas/functions are CELL based, and you would want ALL individual values to have their OWN CELL. Instead of your 4 locations inventory plus total, being in the same cell, you would want each location to have its own cell, and then a seperate cell for the total as well.
That way, you can use formulas/functions to populate totals, and when you update the location for inventory, the totals will auto-calculate based on the updated inventory value change.
With seperate individual values for each cell, you will be able to use formulas/functions.
So what do you have done so far?
Can you upload the file here, so i can have a look?