In which mission do you follow Joshua Kramer to his hideout

There is no way to specifically search for gang hideouts. Hack ctOS centers and towers and hope thatremote profiling will reveal a gang hideout, or hack pedestrians and hope they will reveal a gang hideout.

Some of the storyline missions give you a reputation bonus for completing them with minimal bloodshed. But considering that these aren't repeatable, they are not a sustainable way to fix your reputation.

The best way to do so is to prevent crimes. Note that you get a greater reputation bonus for both taking down the criminals before they hurt the victims (but not before the "Crime propability" bar turns red and the "Suggestion: Intervene" HUD message appears - you won't get any reputation bonus when you scare away the criminal too early) and for performing a melee takedown on the criminal instead of just killing them. There are three different ways to notice crimes:

• Remote profiling crime reports you get automatically while being in an area with unlocked ctOS connectivity
• When you profile pedestrians you will sometimes find people with a "potential crime in progress" description. Scanning these people will also trigger a crime report.
• Sometimes people will perform spontaneous roberies on the street. You notice this by an enemy-icon suddenly appearing on the minimap

You are more likely to find the latter two in areas with a high density of moving pedestrians, like parks or the promenades near the water. The pedestrian-density seems to be higher during the day than at night. Also keep in mind that none of these events happen when you are currently on a mission.