All our babies shared rooms, and some still do. There is a psychological benefit to having another warm body in the room at night. The result for our seven is that they are happier, less prone to be "loners" and have learned tolerance of others as well as how to share everything, including their space! I'd encourage you to rethink keep the baby in a bassinette in your room initially, though. I found I actually got more sleep, as did my husband, if I wasn't constantly having to get out of bed, but could just reach over on my side, attend to the baby's needs (I even had a tiny light on my side - not enough to wake anyone) and go right back to sleep. We kept all ours in our room until they outgrew the bassinette (and our last, who is adopted, was with us in a crib, until he was about a year old). The alternative would be to make yourself a sleeping area in the children's room, so you can stumble in, attend to their needs, and drop right there, since you will most likely have to get up a number of times per night, at least for awhile. My husband is a pilot so there were nights when I slept on the couch with the baby, since his sleep prior to a trip could not be interrupted. Also, we never told any one child that a room was "theirs" until they were teens, that way they never felt too territorial about it. Sometimes the baby would nap in my room in a portacrib, to allow the other children access to their toys during the afternoon. At other times we would move the toys to the living room or den, and make the bedroom just a sleeping and clothing area. In nice weather they were sent out to play during nap time - the possibilities are endless but the best thing is to never cultivate a "mine" and "yours" attitude. The whole house belongs to the family, and as needs change, usage must change, for the betterment of all. Fostering a community spirit when they are very young helps tremendously when they go away to college and/or get married!
Homeschool SAHM of seven, 23yr - 17 mo. One married, one in college, one graduating high school in May, four more adopted and sharing rooms ina small house. They all enjoy each other and rarely fight, because they have learned how to share.