I found a very small hole in the wall, pointing toward the dressing area and mirror, with what looked like a tiny orange tube inside. It looked like there could be a hidden camera in there, and this was obviously a very distressing thought, so I plugged it with toothpaste (which was all I had to work with). Reported it to reception when I left, and they said they'd check it out. I haven't heard anything from them since though.