Not for me. The 3 stars got irritating. I found a quick, easy, no-cops way. I also had Zero Desert Eagle skill.
Go to your house in Grove Street. Make sure there's a car in the garage. When the Garage door opens, open fire until it catches alight (6 shots with the D'eagle). Run away and let the garage door close so it doesn't blow. Repeat this until you get Hitman. I got Hitman really quickly like this.
Every time you shoot something valid (Car, Bike, Person), it's 3 points. At least that's what it was with the Desert Eagle, and I assume so with the other guns. Headshots don't give extra points, nor does anything else.
But anyway, try that method, so much quicker than anything else I used.