When Michael comes home at the end to find Fiona sitting on his stairs, he tossed his keys to his left. Moments later when Detective Paxton knocks at the door, Michael turns to answer it and he tosses the keys again.
Brennan points a gun at Nate's head and then the camera goes to Michael. You hear the sound of a hammer being cocked, but when the camera goes back to Brennan, the hammer is in the un-cocked position..
Michael uses an improvised 'cantenna' to amplify a Bluetooth signal, to hack into a remote cell phone. This wouldn't be possible, as Bluetooth requires two way communication to set up a connection in the first place ('handshake') and the remote phone itself is not amplified for that distance.
One of Michael's tasks is to get a voice recording from a guy with security clearance. When Michael uses the hot-wired car to crash into the subject's car, you can see the camera in the back seat when he spins it around.