The brochure that Leigh finds in the apartment for the "surveillance" microphone, is an AKG D-528 microphone which requires a cabled connection. A wire would have had to be run all the way to her apartment for the microphone to work.
All of the telescopic scenes show the viewfinder cross-hairs off-center with the center point down and to the left. Apparently this was the only way to make enough room to fit the target on screen without cross-hairs covering it up.