One thing that works well to hold small things and not get much notice is an eye glass case.I have a hard padded one from the dollar store,rounded corners made to carry with comfort in mind.
Holds more and longer things than an Altiods tin,easy pocket carry and blends in just fine.
A small folder can help a lot in a highrise,I use mine quite a bit to slide back the latches on doors.I'm sure all the stairway doors lock from the stairways on every floor except the ground floor where you work as this is sop in most buildings,but sometimes you may have to exit at another floor.Also there is often passageways with locked doors used by maintainance etc. they may be a better way out or around something.There are also underground parking lots that are for the "bigwigs" to use that have locked doors that may also provide a better way out.you may be surprized how easy it is to slide the latch back on these doors with a folder and get out.