If you have off campus housing in houses, find one of those houses to rent and move a bunch of folks in. Once you start living there, it will become the "XYZ" house, because it's where many will live, where you hold events, etc.
We rented a house for ours, and it was a pretty decent house. We had 17 women live in it (it was both sides of a double), and it worked out just fine. Make sure though you get a good landlord, because with all those girls in there, you'll need stuff fixed
