Sequence 8 - Necessity, Mother of Invention
You are going to a new district of Venice. Go to Santo Stefano. 
Sequence 8 - Birds of a Feather
You need to listen to a Templars conversation. Move between people that will help you not to arouse any suspicion.  Now hire courtesans and go to the bridge. 
Then hire a second group of group of women and move on - focus on the soldiers on the road.  You will find yourself in a large square. 
Follow your enemies and hire some thieves that are wandering here. When Templars will be under the gate guarded by some soldiers order to distract them.  Wait around the corner. 
Follow these officials and run to another bridge - guards will come from the opposite direction, so jump into the water.  As soon as soldiers will pass you, hide between courtesans around the corner. 
Once again hire girls to distract the guards. As a matter of fact you will be able to listen the conversation.  Hide among other people and wait until the Templars will be moving forward. 
Around the corner they will stop for a moment so do not get too close.  Targets will soon move on - run and hide in a group of people before they will get close. 
Hire courtesans - they will distract many guards at one time.  When you will be at the next bridge stop for a moment- Templars will again look around.  You will hear the whole conversation - then Ezio will lose his opponents. Now go to the villa and speak with Rose.
Sequence 8 - If At First You Don't Succeed
Speak with Rose.  Follow Antonio he will lead you to the palace. 
Climb on a nearby tower  and then to the another one.  Now you can see the whole palace.
Go down to the street and enter the nearby basilica.  Antonio will advise you to climb up on it so do it immediately. 
On the roof of the basilica run to the fence.  You will learn that it is almost impossible to get to the palace in a conventional way. Fortunately, Ezio will remind himself about Leonardo - go to his workshop.