Kill Union Enforcers

Killing both enforcers will lower the difficulty of the racket's hideout/hq.

Roberto “Bubs” Albano

He is located at the back of a market area, beating up a worker. You can sneak around to get a clean shot then easily pop his head off clean with a sniper rifle then just deal with his henchmen. There's also a sentry nearby but as long as you kill Bubs first, the sentry most likely will join the firefight instead of calling for reinforcements.

“Stitch” Gallo

Head to the marked location to find this enforcer abusing another poor worker. Like before, there's a handful of guards and a sentry. If you have the sniper rifle equipped, you can get a clear shot from many possible angles without the risk of the guards discovering you prematurely.