I would recommend against using locations. There are performance considerations to doing this because your location list can get into thousands and tens of thousands. It might be workable if you disable hierarchy for the Locations Organizational View, but if you were planning on using locations for security, this won't be an option for you.
I would keep Location at a high level (e.g. Region, City, Building, or City, Building, Floor) and create a new resource association to 'Office Location' instead, one which is not enumerated elsewhere or part of a hierarchy.