Grand Theft Auto IV/Assassinations

Once you complete Phil Bell's mission "Truck Hustle," you receive the "High-End Assassin" phone call. The Fixer directs the player to a payphone across the intersection of Odhner Ave and Traeger Rd in Alderney (Indicated by the Assassin's target icon). You can call the Fixer at any time (of course not while any storyline missions are active) and he will give you one of nine Randomly assigned jobs. Also of note is the fact that when the calls over Armor and a Mission specific weapon are spawned over the fence behind the payphone. (It's not required to pick these up, but it is helpful.)

Migration Control
The Fixer wants you to take out a target a top of the Booth Tunnel in Alderney City (more specifically, the helipad). Grab the armor and RPG if you want and head toward the target. Once you reach the target open fire on the Helicopter trying to lift off. This is where picking up the RPG is extremely helpful. If you do use the RPG make sure as to aim it at the top rotor because you might hit the fence and waste a rocket (or kill yourself). Don't aim too high or you might miss it entirely. Once the helicopter is destroyed run up with a weapon and check the radar to make sure the red blip (your target) is dead. If not, well… you know what to do. You will receive a phone call from the fixer afterwards and get your reward money.
 * Reward: $3,000
 * Mission Specific Weapon: RPG

Bailing out for Good
The Fixer gives you the assignment of a high-risk target at the police station in Leftwood. After you get the job grab the armor or weapon if you want and head over to Leftwood. The target is being escorted into a car. You can take him out them or follow them a while, but it's recommended that you take him out before he gets into the car. Because there are police around you are most likely to get one star once you start shooting at the target. Be careful to avoid killing the police officers in the possible ensuing gun fight or you will automatically get three stars and that's hard to escape from. You don't have to lose the police to get the call from the fixer giving you your reward money, but staying put could cause your wanted level to rise.
 * Reward: $3,000
 * Mission Specific Weapon: Combat Pistol

Derelict Target
Three men (your targets) have been lured to an abandoned building in Alderney City. Grab the armor and weapon if you want (this time it comes in very useful) and head over to the seven story building. An Alternate way to complete this mission is to heli-drop on the roof and work your way down. As soon as you enter the target area the targets and the other men there will open fire on you. The first target is on the ground floor but will flee to the basement of the structure. Take him and anyone else out and head up to the upper floors. Each floor has about two to three armed gunmen. It's not required to kill the non-targets, but it helps immensely to not have five people shooting at you. Use cover, first-aid kits, and the explosive propane tanks to eliminate them and the targets. By the time you kill the second target you might receive a star because of all the shooting. Your mission is complete once all three of the targets are dead. Like always, you'll get a call from the fixer and get your reward money after they all lie dead.
 * Reward: $4,000
 * Mission specific weapon: Carbine Rifle

R.U.B. Down
This Assassination might be one of the harder ones. You are to kill a group of people in an alley between a police station and the Terroil plant in Actor Industrial Park. What makes this mission hard is that you have multiple targets and if you don't kill them all before they get to their bikes then you might be chasing more than one of them down. If you have some spare RPG's or if you’re good with the sniper rifle then use them to your advantage. Due note that because it’s in close proximity to a police station, you’re likely to get a star or two. Once you successfully kill all of your targets then you'll get the call from the fixer with your reward.
 * Reward: $4,000
 * Mission specific weapon: SMG

Taken Out
Have you always wanted to ride in a limo? Well, you get to destroy one and its passengers in this action packed Assassination. Once you get the mission then get the armor and SMG although it is very hard to complete this mission with the SMG. You are to take out a limo in a caravan or cars randomly driving around Aldereny City. Once you get to that target you will notice that there are accompanying SUV's with the limo. You do not need to take out the SUV's. As soon as you fire a bullet or ram any car in the caravan they will all become aggressive and evasive and more importantly shoot at you. The best approach to this mission is to either block the car without hitting it or while its stopped at a stoplight then launching a RPG at the limo. A well placed rocket will take out the limo in one shoot. After the limo is destroyed then you'll get the call from the fixer and get your reward.
 * Reward: $3,000
 * Mission specific weapon: SMG

Industrial Action
Have you always wanted to see an oil refinery? Well, you be going to one, but you won't be taking a tour. Head over to the Globe Oil refinery in Actor Industrial Park and be prepared weapon wise beforehand by picking up the carbine rifle and armor. When you get to the target zone you'll find a deal of some sort going on. Head up the metal stairs and the catwalks near the main road. Open fire on your targets with a sniper rife and watch the scramble. Get up close and personal and take out all your targets with your rifle. Don't forget to pick up the duffel bag with $10,000 form the deal before the missions over (it’s on the 3rd. Once you kill all the targets then you will, like always, get a call from the fixer with your reward.
 * Reward: $7,500/17,500 (See below)
 * Mission specific weapon: Carbine Rifle

Hook, Line, and Sinker
From the payphone head over to the red blip along the shoreline in Westdyke. You should probably head over to the LCGC and get a combat sniper rifle before you get to the red blip. At the shore you will find a docked boat. Get in to boat. You will see a tropic boat in the distance. Your target is on that boat. You have two options from here. If you really good with a sniper rifle then by all means shoot from there or move up a little more to get a better shot. The other more action filled way is to trigger the other boat by getting to close and have to gun the down in the ensuing boat chase. Either way you choose after you kill the target you'll get a call from the fixer and get your reward.
 * Reward: $3,000
 * Mission specific weapon: SMG

Dead End
This time the fixer wants you to eliminate target's driving around in a patriot (and possibly a second car). If you have been taking a cab ride to your assassinations or if this is your first one, don't do it unless it’s to a near-by waypoint. Doing so will cause the chase to start as soon as you get out of the taxi and will result in you failing you the mission. Once you reach the target zone chase the patriot into an alley (however, if you manage to kill the driver before. The occupants will leave the patriot and go into a loading bay to take cover.  Depending on which entrance of the alley you used you will be boxed in by a second car.  The occupants of this car will open fire on you if you don't gun them down soon enough.  Once you can get out of the car safely, proceed to eliminating the original occupants of the patriot.  After everyone is dead you get your usual call from the fixer with your reward.
 * Reward: $6,000
 * Mission specific weapon: Carbine Rifle

Water Hazard
This is maybe one of the more authentic assassinations your going to have. You are to take out a target on a boat in the channel between Tudor and Actor. While your most likely not going to need the armor its is of great help to get a sniper rifle because the SMG isn't the best weapon to use. Go to the target zone and get a good vantage point with your rifle (or if you like big explosions a RPG would be good too). You only have to kill the target with the red arrow above him. Kill the target any way your heart desires, but make sure not to miss or it will send the boat speeding away and you failing the mission unless you’re already in a boat. Once the deed is done you get the call from the fixer and get your reward.
 * Reward: $3,000
 * Mission Specific Weapon: SMG