I have an excel file that contains the outstanding customer accounts for multiple locations, each location on its own sheet. Some customers have outstanding accounts at more than one location. I would like to create a single sheet that combines the customers and their outstanding amounts from these, which I could then update monthly.

For example, if customer John has $100 at location A, $50 at location c, and $200 at location F, on the sheet I want to create, it would show John as having $350 outstanding. How could I do this?