[Drizz]

When you go do this mission, come by heli. Exit the heli, and go to the pink marker. The mission will start, then what you do is, take your heli and go on roof of the Mansion.
Start from there its waay eazier to make. All you have to kill on your way is only 4 guys and then Diaz, but if you do it the main stupid way by going from the back of the mansion - you will have to kill like 20 of them.

I found that tip good and made this mission without loosing any hp

[The_Transporter735]

Even though killing 20 men was not a problem this seems to be a very good idea to consider if u wanna escape the troubles. i must say getting into the main hall is a problem for me cause the men have the advantage of hiding so ur way is pretty sleek to get back at them.