This is a definitive checklist to achieving 100% in Grand Theft Auto IV. I've personally confirmed all of these tasks. Feel free to reply if you think something is inaccurate. There are gameplay spoilers in this thread!

Good luck!

• Complete 90 story missions and reach the game's credits, irrelevant of choices made and ending received (60%).

• Win in a full game of bowling (1.25%).
  
• Win in a game of darts (1.25%).
  
• Win in a game of pool (1.25%).
  
• Beat the high score of 10950 in QUB3D (1.25%).

• Complete all 50 stunt jumps (2.5%). (see also: Unique Stunt Jumps Video Guide)
  
• Kill all 200 pigeons scattered around the city (2.5%).
  
• Find and steal all 30 cars requested by text message from Stevie (2%). (see also: Maps)

• Raise friendship with Little Jacob to 60% to unlock his special ability (1.66%).
  
• Raise friendship with Brucie to 70% to unlock his special ability (1.66%).
  
• Raise friendship with Packie to 75% unlock his special ability (1.66%).
  
• Go out with Little Jacob, carrying out every available option at least once (1.66%).
  • Darts
    
  • Drinking
    
  • Eating
    
  • Pool
    
  • Show
    
  • Strip Club
• Go out with Brucie, carrying out every available option at least once (1.66%).
  • Boating
    
  • Bowling
    
  • Drinking
    
  • Eating
    
  • Heli Ride
    
  • Show
    
  • Strip Club
• Go out with Packie, carrying out every available option at least once (1.66%).
  • Bowling
    
  • Darts
    
  • Drinking
    
  • Pool
    
  • Show
    
  • Strip Club

• Complete all tasks given by random characters met in the street (5%).
  • Badman
    
  • Brian (3 encounters)
    
  • Eddie (2 encounters)
    
  • Gracie
    
  • Ilyena
    
  • Hossan
    
  • Marnie (2 encounters)
    
  • Mel
    
  • Pathos (2 encounters)
    
  • Sara (2 encounters)
    
  • Note: You do not have to meet Cherise, Clarence, Ivan or Jeff. Their tasks do not contribute toward 100% completion.

• Kill all 9 assassination targets (2%).
  
• Set a time in all 9 street races given by Brucie by finishing in first place (2%).
  
• Steal all 10 "Exotic Export" cars requested by email from Brucie (2%).
  
• Complete all 10 deliveries for Little Jacob (2%).

• Kill 20 criminals in in the "Current Crimes" side mission (cumulative over all islands) (2.5%).
  
• Kill 30 criminals in in the "Most Wanted" side mission (10 per island) (2.5%). (see also: "Most Wanted" side mission tips)

Spoiler: Reward for reaching 100% in the "Game progress" statistic
---
Ammunition cap lifted
You can purchase as much ammunition as you like from the gun stores scattered around Liberty City or from Little Jacob. Note you do still need to earn the cash to buy the ammunition with beforehand.

There does not appear to be any in game message or unique prize for achieving 100% game completion. All you unlock is the minor ability above. Achieving 100% does, however, gain you entry into the "100% Club" leaderboard at the Rockstar Games' Social Club. This is providing you have registered at the Social Club and linked your Xbox Live Gamertag to your profile.

Spoiler: Reward for killing all 200 Flying Rats
---
"All diseased pigeons killed. LC is a cleaner place."
An Annihilator attack chopper now spawns on the helipad at the top of the very tall MeTV building on the corner of Kunzite Street and Denver-Exeter Avenue in Star Junction, Algonquin. This star shaped helipad is illuminated by purple lights in the evening. The building itself is easily identifiable at street level as it has a rotating MeTV advert on a faux vinyl player on its wall. It also has several movie posters and an open car park garage at its base. The easiest way to get to it is to steal a Maverick helicopter from the Helitours and fly toward the Comedy Club.

Spoiler: Reward for completing Stevie's car boosts
---
South Bohan garage open
The South Bohan garage will now offer money for any vehicle you deliver. The better the condition, the more money you will earn.

Spoiler: Little Jacob's special ability (unlocked at 60% friendship)
---
Guns
Little Jacob parks in a nearby alleyway and sells you discount priced guns from the trunk of his car.


Spoiler: Brucie's special ability (unlocked at 70% friendship)
---
Chopper
Brucie lands his helicopter nearby and takes you to fixed destinations on the map.


Spoiler: Packie's special ability (unlocked at 75% friendship)
---
Bomb
Packie brings you a bomb that you can place on a car and detonate with your mobile phone.

• Key To The City (100G): Achieve 100% in "Game progress" statistic.
  
• Assassin's Greed (20G): You completed all 9 assassin missions.
  
• Cleaned The Mean Streets (20G): You caught 20 criminals through the police computer.
  
• Courier Service (10G): You completed all 10 package delivery jobs.
  
• Dare Devil (30G): Complete 100% of the unique stunt jumps.
  
• Dial B For Bomb (10G): You unlocked the special ability of Packie's car bomb placement.
  
• Driving Mr. Bellic (10G): You unlocked the special ability of Roman's taxi.
  
• Endangered Species (50G): Collect every hidden package in the game.
  
• Fed The Fish (5G): You completed the mission "Uncle Vlad".
  
• Full Exploration (20G): You unlocked all the islands.
  
• Gracefully Taken (10G): You completed the mission "I'll Take Her".
  
• Impossible Trinity (10G): You completed the mission "Museum Piece".
  
• King of QUB3D (15G): Beat the High Score in QUB3D.
  
• Lowest Point (5G): You completed the mission "Roman's Sorrow".
  
• Manhunt (15G): You completed the most wanted side mission.
  
• No More Strangers (5G): Meet all random characters.
  
• Off The Boat (5G): You have completed the first mission.
  
• Order Fulfilled (10G): You completed all 10 Exotic Export orders.
  
• Pool Shark (10G): You beat a friend at pool.
  
• Retail Therapy (10G): You unlocked the special ability of buying guns from Little Jacob.
  
• That Special Someone (10G): You completed the mission "That Special Someone".
  
• That's How We Roll! (10G): You unlocked the special ability of Brucie's helicopter ride.
  
• You Got The Message (20G): Deliver all 30 cars ordered through text message.
  
• You Won! (60G): You have completed the story.

You sir are jesus in a box.

Xenctuary - Second island, south, 4th dot from the bottom, the one that is the top of the < pattern, that is the Faggio moped, Stevie's first request. $2310 for perfect condition delivery. Quick access is to get a taxi to the Chinatown Weapons Store and then just walk south to the main street that goes left and right. The Faggio is on your left, parked on the street, you may not see it immediately due to all the trash cans on the sidewalk. Perfect Delivery: $2310



This message was edited by Kuduros on May 03 2008.

Nice one, I'll add it in now. I think the Stevie's car requests may be handed out in a random order since my first target was the Comet.

Stevie's Requests

Cavalcade
Coquette
Dilettante
Dukes
Faggio
Freeway
Huntley Sport
Infernus
Manana
NRG900
Rancher
Rebla
Super GT
Turismo
Voodoo

Quick Access - Get a taxi to the Westdyke Car Wash. Go straight on through the traffic lights and down to the coastal road. Take a left here and follow the road past the AM2PM service area. Turn right and then at the junction, you'll see Gozushi on your left and if you look immediately right, the Cavalcade is parked in the driveway of the house next to you.

Map Location Help - Secondmost northern dot in Alderney. Show me the map


Perfect Delivery: $23100

Quick Access - Get a taxi to the Chinatown Weapons Store. Go north up to the end of the street, then turn left and walk west across the street. When you hit the People Restaurant on your left, turn right and cross the road, then walk north up the street ahead of you. When you reach the intersection, turn left and walk west down past the roadworks to the large intersection. Directly across is a large RANCH store with a white and red sign, cross over to it, being careful if you're on foot as this road is busy. Go up to the north end of the street, under the scaffolding to the next intersection. Ahead of you, you'll see THE DAILY GLOBE, just so you know you're in the right place.

Turn left here and walk along the street in a west direction. Keep going past a branch of the Bank of Liberty until you get to a City Hall looking place on your left and a burger stand on the sidewalk. Turn left down this street to head south down towards a Superb Deli (white sign). As you head down towards it, you'll see a huge chapel/church towards your northeast. The Coquette is right outside, parked on the street. The Coquette is alarmed so watch out for police when you break the window.

Map Location Help - Southern region of Algonquin, near the western coast. Show me the map


Perfect Delivery: $13530

Quick Access - Get a taxi to the Willis Car Wash. Grab a car this time to travel in, then head north. Look out for RANCH's banner signs hanging from a building on the right hand side of the road, they're huge and black and white, you can't miss them. When you see them, turn left into the junction here and the car you need is parked on the right hand side of the street.

Map Location Help - Dukes area of the city, near Francis International Airport. Show me the map


Perfect Delivery: $6600

Quick Access - Get a taxi to Modo Clothing in North Holland. Cross the street east and just over the brow of the hill, the Dukes is parked.

Map Location Help - Most northern dot on the Algonquin island. Show me the map


Perfect Delivery: $7260

Quick Access - Get a taxi to the Chinatown Weapons Store and then just walk south to the main street that goes left and right. The Faggio is on your left, parked on the street, you may not see it immediately due to all the trash cans on the sidewalk.

Map Location Help - It's on the second island, down in the south, 4th dot from the bottom, the one that is the top of the < pattern. Show me the map


Perfect Delivery: $2310

Quick Access - Really simple one. Get a taxi to the Willis Car Wash. The Freeway is parked outside on the kerb.

Map Location Help - It's in Dukes, just west of Francis International Airport. Show me the map


Perfect Delivery: $6600

Quick Access - Get a taxi to the Northern Gardens strip club. The LCPD station mentioned in the text is on the corner of the T-junction directly NW of the Strip Club icon. The Huntley Sport is in the carpark. You'll have to head to the respray shop from here if you want a Perfect Delivery. The police are currently watching you and when you take it, they'll almost certainly shoot it or you'll damage it in your escape.

Map Location Help - It's in Bohan, the northernmost dot on the entire map. Show me the map


Perfect Delivery: $13200

Quick Access - Get a taxi to the Downtown Weapons Store in Broker. Make your way south down through the alleyway to the park. Cross over the street and head left, in an eastern direction up the hill. At the top of the road, you'll see the archway from the photo Stevie sent on your right. Look left, across the intersection. You'll see a DENTAL building. The Infernus is right outside it.

Map Location Help - Middle of Broker, second dot from the bottom. Show me the map


Perfect Delivery: $33000

Quick Access - Get a taxi to the Cluckin' Bell on Cerveza Heights. Head east and keep watching for an intersection with Ben Chow Mortgage on your right. You'll know it when you see it, there's a rundown Burger Shot just across the street from it, also on the right. Turn right here and park in the back of the Burger Shot. The Manana is in the parking lot with you.

Map Location Help - Back on Dukes for this one. It's near the expressway. Show me the map


Perfect Delivery: $3960

Quick Access - Get a taxi to the Middle Park East safehouse on Albany Avenue then drive or walk north up that main road til you see the LCPD station across the street from you. Turn left here, walk up to the first turnoff to the left and the NRG900 is parked just off the street on your left.

Map Location Help - It's on the second island, up at the top, the dot just a few blocks southeast from the Dukes marker. Show me the map


Perfect Delivery: $8250

Quick Access - Get a taxi to the Port Tudor Pay 'N Spray. From the corner of the street, turn and run east across the road and hop over the wall, it's a safe fall. Go down the grass embankment and keep heading east towards the water, down between the buildings (eCola on your right, some other building on the left). Head down past the warehouses A and B on your left, then turn left at the corner of B and head up the right hand side of it, to the north. The Rancher is parked at the northeastern corner of this building in the parking area, where there are probably dock workers standing chatting. Be careful driving out of the dock district, there's a lot of large HGVs about that will *bleep* it up.

Map Location Help - Third island, southernmost dot is the Rancher. Show me the map


Perfect Delivery: $8250

Quick Access - Get a taxi to the Cluckin' Bell on the Triangle. From the Cluckin' Bell, walk down south and round the corner then head east to the main street. Turn right and head south, looking on the left hand side of the street at the parked cars. In about a block or so, there is a Rebla parked on the street outside a building with a glowing green crab sign. It's alarmed and on a very busy street so watch for police before busting the glass.

Map Location Help - Second island, just north of the Faggio and Coquette. Show me the map


Perfect Delivery: $11550

Quick Access - Get a taxi to the Chinatown Gun Shop on Algonquin. Run south past some construction work/scaffolding until you reach the intersection with Liberty City Telecom and Super Real Jewellery. Turn right and run east along the road until you see the 69 Exchange on the left side of the street. The Super GT is parked on the street here next to you. It's a powerful little bitch so be careful on long acceleration stretches, as it's hard to get slowed down, especially if you're after Perfect Delivery.

Map Location Help - Second island, southern end. This is the middle part of the < pattern making up the Faggio, Super GT and . Show me the map


Perfect Delivery: $36300

Quick Access - Get a taxi to the carwash just off Cassiar Avenue. Run south down the street to the first turnoff on the left, then turn into the first house driveway on the left. The Turismo is parked outside the house here, it has an alarm so be careful of police before busting the window.

Map Location Help - Third island, top dot is the Turismo. Show me the map


Perfect Delivery: $36300

Quick Access - Get a taxi to the Steinway Darts Club. There's a printing store across the street to the east. From there, go south down to the end of the street and turn left, you should have a branch of the Bank of Liberty on your left. See the massive building across the street? That's the building Stevie mentioned in his text. The Voodoo's right outside, you should just about see it from where you are.

Map Location Help - Almost in the middle of Dukes and quite far west from the Francis International Airport. Show me the map


Perfect Delivery: $6600

[b]Quick Access - .

Map Location Help - . Show me the map


Perfect Delivery: $

Great, we'll have the car boosting map completed in no time! I've also added the list of achievements you unlock on the way to 100%.

The one in Boabo is a Contender, the one between the Manana and Voodoo. Also, the drop off isn't where you've labelled it. It the one with a question mark, sothernmost on Bohan.

Tidied up my post and compiled it. Rancher's been added but it's already on the map.

Thanks guys. And I'm not sure how I managed to put the drop off all the way up there Tec 9. That's a strip club! It's been fixed.

Coquette added, not named on the map yet. The dot is 10pm from the Faggio and intersects directly south from the m in Comet.

This message was edited by Kuduros on May 03 2008.

I'm continuing with the car boosting now, so hopefully we should get a full map tonight. I also just confirmed that QUB3D is required for 100% completion. It increases your overall percentage by 1.5%. I managed to get 12800 points, but the game screen will glow as soon as you reach the score required.

Rebla added, not on map.

This message was edited by Kuduros on May 03 2008.

The checklist is now finalised. Each section's percentages add up as expected. The figures should all be correct, but do post if your experience differs.

In regards to the car boosting map, I've completed it as much as possible. Since I've now unlocked the related achievement, the two unknowns currently on the map must have been from before I started to mark down the locations. If anyone finds them, let me know and I'll add them in.

Several achievements that I have unlocked:

One Man Army
You survived a 6 star wanted level for a full 5 minutes.

Walk Free
You successfully lost a 4 star wanted rating.

It'll Cost Ya
You made a taxi trip from one island to another without skipping.

Warm Coffee
You were invited into your girlfriend's house.


Don't know if they help you at all or not, but I figured I'd add them in just in case

I need some help with a perfect delivery Dukes, I managed to *bleep* mine up, I think it took a bullet during a police escape. Let me know if you find out how much the perfect delivery Dukes is, I'd appreciate it.