CIA level spy camera - a dot on the wall
This is transmitting to a series of repeaters. One next door or if next door is further away, to a local repeater - your router usually - or some low voltage repeater which sends it next door. Where the feed is recorded both on local hard drives and live streamed to all relevant parties spying on you.
You will never find them all. Even if you try. They will just replace them once you leave the house with twice as many.
These are in your car, truck, house shed, backyard, driveway. Every angle is vectored is over killed with this tech. This includes audio so good, they can count your breath from 30 feet away.
This is 20 year old tech. I knew about it IN THE 1990s.
It's nanotech and they have stuff way smaller than this.
It's in every TV, monitor, cell phone, all of it. Your sunglasses, behind every mirror...
You COULD if you were so inclined, go around with a toothpaste and squeeze a smidgen and wipe every black dot you find. Great way to kill a day of time. Get a ladder; they love ceilings.