Tips for the "hard" missions:
1) Unless you just _have_ to beat a mission the first time you play
it, take it slow. Sometimes it pays to just follow your target
around, and see where they go. Sometimes they get out of
cars, walk around ,etc. "Sir, Yes, Sir" is the best example of
this.
2) Know where you are going/what you are doing. If you fail
a mission, don\'t go back to it right away. Try and find a helicopter
or fast car, and just cruise around where you were. You\'ll get
an idea of how many cops are running around, if there are any
health/bribe icons close, etc.
3) Use stealth. It\'s surprising how much stealth comes into play
in this game (for me it was, at least). In the mission you are
talking about (the one where you have to kill 8+ people), it pays
to be stealthy and kill from long distance.
4) Lock, load, and destroy.
Seriously, it pays to kill a bunch of
peds for their money, buy all the ammo/armor you can, and then
go to your mission. So many times I said "Eh, I\'ll just get by
with 100 health and no armor," only to fail the mission again...
5) Be creative. There is more than 1 way to complete these
missions (90% of them, anyway). Use a little creativity, and it
might be easier than you think.
6) Cheat. Not for everyone, but if you\'re frustrated to the point
of breaking a controller, just ask for help, or use a cheat code...