As usual, always kill the enforcers first before going to the major operations of the current racket you’re trying to take over to lessen the security and difficulty.
This is another easy kill. Just circle around away from the lookouts then snipe him from a distance. Or, take out the lookout behind him and take cover behind him to finish him off with a grenade or close-range hail of bullets.
This one is very easy to kill. First, take out the lookout then shoot the explosive barrel near the target and the sentry to kill most of them in one shot. The target may survive the initial blast so you have to finish him off. Finally, pick off the survivors until they’re all wiped out.