Hi jll,
I just lurk, but was a little surprised by how you have been treated on this thread. It might not be a good idea for your daughter to ask about costs during the parties -- but I hope your daughter isn't worrying about this reality in addition to the stress of this exhausting week!
I know a number of parents who have greek daughters there currently, many in chapters you listed, and $2400 sounds about average (certainly not at the low end) per semester for the first year.
I have never heard of any dues approaching 4K per semester -- ever -- from any other parents. I'm not sure what effect new construction has (or will have) on member costs -- though I'm sure this hasn't doubled costs for the actives.
Now
fraternities there are a different matter -- according to my friends who howl about those house bills -- the costs do far exceed the sororities. Has any of your information has come from parents of guys?
Good luck to your daughter. I think you will be okay.