Hitman: Contracts/Slaying a Dragon

The Quick Way
Head to the apartments. The entrance has glowing green lights. Walk around and you should see it. Now go to the 4th floor. Take out both the blu lotus members silently. Go inside and take out your sniper or use theirs. Kill the red dragon leader by sniping through the window, and head for the exit. You are done.

On a side note: Make sure to disguise as a blue lotus before you go outside. Sometimes the enemy wil know you killed the target.