Holy guacamole, this was tense! It was a close call for me, on the way to the elevator, the glowing eyes scary man was right in front of me before I just managed to escape into the cupboard.
Using the geiger counter to signify if the monster is close was a cool idea. The only thing I'd note is that when reading, the gameplay should pause. I could not finish reading the note in the eviction notice room because the crackling was getting crazy and I didn't want to stay around to find out what happened if you meet the cause. I also thought the moving painting was neat, that one got me good when I first entered the room. Regarding the visibility range, I have no strong feelings, although I actually think it helps make things scarier and feel more claustrophobic, which I think is good in a horror game set inside.
All in all a very polished well-executed spooky game. PLUS it contains an audio clip of you saying "love you", instant 10/10.