After having played and finished this game on PC, I found it on 360 and have been playing it again, great game. The bulk of the achievements could be unlocked in under 15 hours if you did not mess around and explorer too much, like I do, just worked through the missions and story, but to complete and finish the Corleone Challenges would take a lot longer.
This game has cheats that do not affect achievements.
Enter the following at the career progress screen:
Full Ammo : Y, Left, Y, Right, X, Right (3)
Full Health : Left, X, Right, Y, Right, Left (3)
Film Clips : Y, X, Y, X, X, Left (3)
ACHIEVEMENT GUIDE
First Sign of Respect - 5 points
Reach Respect Level 10
See Public Enemy Number One Achievement.
Gaining Respect - 10 points
Reach Respect Level 20
See Public Enemy Number One Achievement.
Making an Impression - 15 points
Reach Respect Level 30
See Public Enemy Number One Achievement.
Demanding Respect - 20 points
Reach Respect Level 40
See Public Enemy Number One Achievement.
Jack of All Trades - 25 points
Reach Respect Level 45
See Public Enemy Number One Achievement.
Public Enemy Number One - 50 points
Reach Respect Level 50
You will get these just by playing through the game, taking over and eliminating rival families, robbing banks, hijacking the racket trucks will gain you respect.
Assassin - 10 points
Earn 5 Execution Styles
Pretty easy this, simply use different weapons and when the 'execute' prompt appears press LB to execute. Hardest thing is remembering what 'Execution
Executioner - 40 points
Complete ALL Execution Styles
The next one from the above, complete all execution, again, trying to remembering what 'Execution Styles' you have already done is the hard part.
Petty Theft - 10 points
Crack 10 Safes
Pretty much all businesses have a safe, you need Dynamite to open it, open the map screen, press RT to see a list of businesses, scroll through them and you should see Safe Opened: No, go there and open it, if you do not own the business, take it over.
Safecracker - 30 points
Crack ALL Safes
The next one from the above, find and crack open all safes in the game, 100 of them if I remember correctly.
Negotiator - 5 points
Bribe a Police Chief
Have a look on the map for a Police badge, not FBI badge, go there and offer the guy some money.
Smuggler - 10 points
Hijack 10 Racket Trucks
This is tricky on the Xbox 360 version of Godfather, have a look around for Trucks driving around that are in rival family colour, stop it by parking a car infront and open fire. Men will jump out of the back, once their dead the driver will jump out. Use some persuasion to give you the keys, now get the truck back to your safehouse or another drop-off point (marked on your map) as quickly as you possible can, you will be chased and under fire. Do this 10 times, Tip: try to do it as close to your safehouse as you can to make it that little bit easier.
The PC version was different in that you only had to pickup the money bags and get yourself back to your safehouse, not the whole damn truck.
Real Estate Investor - 10 points
Purchase a Safehouse
You get this automatically after you complete one of the first missions in the game, cannot remember which one now off the top of my head.
Real Estate Mogul - 20 points
Purchase/Own ALL Safehouses
The first one you will be given through the game, the rest you will have to buy yourself.
Bodyguard - 10 points
Hire a Crew Member
Earner - 10 points
Extort 10 Businesses
You will get this by playing through the game, that's the point of the game anwyay.
Enforcer - 10 points
Take Over 5 Rackets
Same deal as above, you will get this by playing through the game.
Arms Dealer - 10 points
Purchase a Firearm Upgrade
While getting Film Reel number 4, see below, there is a 2 Star Weapon Dealer, if you have the money buy an upgrade. Note: depending on the time of day/night, you may come under fire.
Demolitions Expert - 10 points
Bomb a Business
Find a business that is owned by a rival family, you must have a Bomb, not Dynamite, run in and plant the Bomb then get out of there. I would suggest that you KEEP RUNNING all the way to the closest safehouse, or else...
Entrepreneur - 15 points
Collect 10 Film Reels
You can get this one early on in the game, there are 10 reels that are easy to get without coming under fire.
Start at the Corleone Compound:
1. Exit the compound, straight away look right, should see one behind a tree.
2. Go right into Allen St, left into Thayer St then into Charles St, should see one infront of a gate.
3. Go right into Canal, left into Broadway, first left again, down the end behind some stuff.
4. Turn around, right into Broadway, follow all the way to the end, a 'circular' road, back left corner, behind a newspaper stand.
5. Go back along Broadway, second right into Chambers st, alley on the left, should see it in the corner.
6. Go left out of Chambers, right into Park, there is an FBI agent close and a Bomb Dealer at the front of a white building, look behind the pillars.
7. Go out to Worth and go right, then go left into Bowery, follow this to East Houston and go right. Newspaper stand on your right, look behind it.
8. On your left in an alley, leads back to Bowery, past the Shotgun Dealer, near the back of the rival family business, wooden dumpster near steam vent.
9. Left out of the alley into Bowery, right into East Houston, right into Mott (towards the hospital), at the stairs look left.
10. Head back into Mott, go left into Prince, left into alley, follow stairs to the top to find another Film Reel.
Another one for a bonus:
11. Turn around and back into Prince, go right past the Church, just before the rival family business is an alley, leads to a smaller alley, follow this to the end.
Debt Collector - 30 points
Collect ALL 100 Film Reels
Well you have the first 11, just another 89 to go huh? Have fun.
I would suggest leave this until near the end of the game, after you have taken over all the rival businesses and rackets, or at least until you have control over all businesses and rackets in one area of the map, this will give you a better chance of collecting them all without coming under fire all the time.
Neighborhood Control - 20 points
Take Over a Neighborhood
You will get this playing through the main story missions.
For the Family - 25 points
Complete ALL Missions
Same deal, you will get this by finishing all the main story missions, the blue circles on your map.
Contract Killer - 25 points
Complete ALL Hits
Again, you will get this by finishing all the hits, the yellow circles on your map.
Service Provider - 25 points
Complete ALL Favors
You will get this by finishing all the favors, the pink circles on your map.
Diplomat - 20 points
Help ALL Merchants
As you are taking over all the businesses, you may find one that needs a favor, help them to get this, there are 10 merchants that need a favor.
Total Domination - 50 points
Extort ALL Businesses
See Rival Family Elimination Achievement.
Front Man - 50 points
Take Over ALL Fronts
See Rival Family Elimination Achievement.
No More Narcotics - 30 points
Bomb ALL Drug Rackets
See Rival Family Elimination Achievement.
Warehouse Wrecker - 30 points
Seize ALL Warehouses
See Rival Family Elimination Achievement.
Transport Takedown - 30 points
Seize ALL Transport Hubs
See Rival Family Elimination Achievement.
Rival Family Elimination - 40 points
Destroy ALL Rival Compounds
With this and all the others above, you will get them as you progress through the game, you have to do these to progress anyway so you cannot really miss or skip any. The Don of NYC Achievement requires all these to be done.
Forced Entry - 10 points
Heist a Bank
See Bank Robber Achievement.
Bank Robber - 10 points
Heist ALL Banks Once
There are 6 Banks on the map, marked with a $ sign, after you have robbed the sixth (6th) one you will get this. Of course you do not have to rob all 6 in one go, make sure you have a safehouse close by, wait until you have purchased them all, better weapons help too.
Knockout King - 15 points
Win a Prize Fight
See Heavyweight Champ Achievement.
Heavyweight Champ - 25 points
Win ALL Prize Fights
There are 5 Prize Fights in all, you CANNOT use any weapons, wait until you are level 50 or close to.
1. Little Italy - 2nd floor of Molsenni's - Prince Street and Bowery
2. Brooklyn - 1st floor of Pitkin Garments - Washington Street and Front Street
3. Midtown - Basement of Corcoran's Perch - 23rd Street and 4th Avenue
4. Hell's Kitchen - Roof of Stromboli Supplies - Galvin Street and 11th Avenue
5. New Jersey - Basement of Highway Hotel - Observer Highway and Newark Street.
The Don - 25 points
Reach Don Rank
You get this one after you have completed all the main story missions through the game.
Don of NYC - 50 points
Reach Don of NYC Rank
This one however is more time consuming, you must have completed all main story missions, taken over all rival family rackets, businesses, warehouses and compounds, basicly everything to get this, but can be done by playing through the game.