Our company has a main location and four satellite locations.

The main location and the satellites each have their own inventory and max/min requirements.

We currently have a single chart of accounts with a code to differentiate between the locations.

A Partner can be a customer at one or more of our locations, for example if the partner has multiple locations.

Work on the same job is occasionally split between multiple locations.

Some employees will only need access to the database for one of our locations, but other employees need to access all locations.

So, should I set up multiple companies? Should I create a hierarchy pointing to the main location as the parent, or create a holding company with all the locations as children?

What are the caveats associated with multiple companies? I've tried reading through the docs on this, but I don't find them helpful for making this decision.