They advertise and are professionally licensed. Many specialize in counter-surveillance.
Other then the advice to “look”, theres not much you can do.
To do this in a way that will locate well-hidden devices you should hire a professional who owns the right tools.
Otherwise, install kismet and monitor for unknown BLE and wifi signals and use video surveillance to detect people attempting to remove passive devices.
You won’t be able to locate devices that use other wireless technology without specialized tools.
If this is a serious worry then hire a professional
Don’t know such person.
They advertise and are professionally licensed. Many specialize in counter-surveillance.
Other then the advice to “look”, theres not much you can do.
To do this in a way that will locate well-hidden devices you should hire a professional who owns the right tools.
Otherwise, install kismet and monitor for unknown BLE and wifi signals and use video surveillance to detect people attempting to remove passive devices.
You won’t be able to locate devices that use other wireless technology without specialized tools.
If this is a serious worry then hire a professional