I got the easiest assassin medals in Chataeu, the dark building really helps.
Just added a new Medal Guide/Video:
Scoped In/Long Ranger Medals for UC3 Multiplayer
Next Medal Video:
Bargain/Three Kickback King Medals
I may release an updated video that shows all the Long Ranger locations (that I know of) for each map later, but that could take some time to get a kill at each one.