Whao i do next in ins creed brotherhood?

IVe got all of rome exept the entire right side, wich it sais im not allowed to go there yet, i have goten 2 romulus scrolls but cant find anymore. And ive bought all of the economic buildings in the area, ecept the landmarks. Iv did all christina missions, and bough all of leonardos items, and he told me to destroy all of his war machines,AND im guessing they are in the area i cant go in. How do i unlock that area, And im in sequence 3. I left the animus a few times, but just talked to the poeple nothing major??? What am i sopose to do