- Don't hesitate to spend money on weapons, There's nothing you can do in GTA 3 with money except use it to buy weapons. The only two exceptions where money will be required to play the mission are Bomb Da Base Act 2 ($100,000) and the very last mission of the game ($500,000).
- I HIGHLY recommend finishing all kinds of side missions in Portland before you start working for Salvatore Leone. Even if you do not usually play side missions like Vigilante or Taxi, at least finish the Marty Chonks and El Burro's (side) missions as keeping them for later will only make it harder. You will understand why.
- Finish Kenji Kasen's mission first, even if you get stuck on one of his missions and find it hard to complete, still stick to finishing them all and then move on to the others.
- After completing Ray Machowski's last mission, he will give you access to his personal garage where you will find BULLETPROOF Patriot. Store the vehicle in the garage and save the game. Avoid blasting this vehicle off as it will be necessary in missions like Espresso2Go. Without the bulletproof patriot, completing the mission will definitely turn into a nightmare.
- Mafia Sentinel or Sentinel is overall the most comfortable vehicle in the entire game. It's not as fast as the other sports vehicles like Banshee or Infernus but it is the most stable and balanced plus it's a four-seater as well so I recommend using it at least till you get comfortable with other vehicles.