You did everything correctly.

The one other thing I recommend you do is wait until the apartment is dark, turn off the lights, then turn on your phone camera (without flash) and walk around the apartment, pointing your camera at all surfaces. The camera on your phone will pick up infrared - which is used by surveillance cameras to see in the dark.

NOTE: Infrared is also used by some normal devices so don't panic if you spot one or two emitters.

If you find any, then decide what to do from there.