Started as one of those securities wearing funny shirts so I could enter the building before the target (later on I discovered that I could enter the building using the ladders in the back, but eh).
I got to some sort of office, where there's a guy in a suit who first approaches the target. Choked him, hoping that I could disguise as him, but there was no option, so I just dumped him on the crate that was on the same room.
The target and his protegé went to the following room and they started arguing with the lawyer. Target went back to the office and I put a bullet in his head. As I was dragging his body to the same crate the other guy was in, someone saw me. Ran away and escaped in the speedboat.