For each situation,
the right details.
Choose the signs that match your observation. Exact identification and possible methods are matters for the professional you hire.
Not sure what it is?
Simply describe what you notice. Note the location, frequency, possible access points and recent changes. A photo taken from a distance may help when discussing with a professional; do not handle unknown traces to obtain one.
Avoid using several products or moving objects between rooms before seeking advice. Mention measures already taken without assuming they are sufficient.
Let's talk about
what you noticed.
The room, the signs and when they appeared: three useful details for your enquiry.