mets on liver+brain - bones, lungs?

Hi, I am a BC stage IV with mets on liver and brain. I was treated with stereotaxis for brain and I am on herceptin+xeloda to treat liver.
I read this message board often, it help me a lot to understand things in a broader context. I know at this stage there is a strong risk for mets on bones and lungs; to this regard, what is your experience? Should I do a bone scan just to make sure (my last one was more than a year ago). Just wondering what are the best 'moves' before it's too late...
Thanks