Count of Related Record
I am very new at filemaker and would like some help with my database. I have attached an image of the basic Item record detail that most of the work is done to this database. This is the 'home' screen of the database.
When a New item is added to the database the item information represented via TEST is this image is added via a the Item ID. The information is held in a separate Items database and the tables are related by Item ID. Location is determined via dropdown list and is individual to each record.
What I would like to do is have the Amount in office field to be automatically updated as I change the location on individual records.
For instance if I create a new record for a specific type pf latch I would like the amount in office field to automatically update to add one to the current total. If I were to give out a latch to an engineer and change the location to offsite I would like the amount to go down by one.
How would I be able to achieve this. I have attempted a number of different ways but I think I may be stumbling blindly in the dark here .