Assassins Creed Brotherhood help!?

Ok I am right in the beginning of the game on sequence 2 where the mission "easy come easy go" is next in line. I initially declined the mission so I could explore for a bit and renovate some buildings. Now, no matter what, a main mission icon refuses to pop-up. So now im stuck in this tiny part of Roma with nothing at all to do. Also, the Rosa in Fiore mission icon appears on my map but in no way, shape, or form can I get inside the building. This is really frustrating and there is no help about this anywhere on the net. Can anyone help with this?