I suppose it depends on how you define "discrete location"
S.U. is upper level of business building. Principle entrance is off street as opposed to side or rear entrance. Facility is functional and clean. Presuming you have pre-arranged your "date", the lady will greet you on arrival.
If you are really that concerned about discretion, then I would suggest making own out-call arrangement and invite lady to join you at a location of your choice.