Congrats on the acceptance.
BU still hasnt sent us the official academic calender, so Im not exactly sure what day classes begin.
As far as housing, BU doesnt have dorms, so you will have to find housing on your own. Im guessing that you arent doing EXCEL, so in that case, it may be wise to come to Boston in advance to try and find a place to live. If you are looking for a roommate, you can visit the BU website and fill out some sort of roommate matching form.