As others have said, dues can vary widely. Your first semester will be the most expensive and can top $1000 - you will have dues, initiation fee, badge fee (which varies widely according to how plain/elaborate a badge you get), and possibly a few other one-time fees. After that, it should settle out to no more than a few hundred per semester.
The chapter's treasurer should be willing to work out payment plans. She should also be willing to let you know, at least in general terms, where the money is going.
At some schools, it's considered tacky to ask about dues - the thinking is that if you have to ask, you can't afford it. I suspect PSU is not among them. My school certainly wasn't - PNMs could pick up financial information sheets from each sorority that gave the breakdown of first-semester dues and dues for subsequent semesters.
HTH
