Turn off the lights and use your phone camera and look for a dim light. They usually have an infrared bulb to see at night.

I have a habit of using a flashlight to go to the toilet in hotels or unfamiliar places, so I don't stub my toe or other stupid stuff when doing the nightly toilet sleep walk.

So I grab the flashlight, point it around and notice a glint from the ceiling fan. The ceiling fan didn't have an IR remote so it didn't make sense and yup, sure enough it was a little lens that conveniently pointed towards the bed.

Fun thing: We actually signed a waiver that the house uses cameras, since there were a view regular ones on the perimeter for security, which seemed logical. That asshole really tried to play the "but you signed that you're okay with being filmed" card.

Look for things that point to the bed or shower that don't need to. Fire alarms, lights, and chargers are common options. Check Amazon for common options. Also try shining you phone flashlight on them, lenses will reflect well and must be exposed obviously. They may be tucked into holes, but they still have to see something.