The typical dorm will cost a student about $3,100 per term if food is included. To contrast, the most expesive fraternity is only $2,600 per term. A detailed cost comparison can be found here.
Many fraternities will "buy out" a student in the resident hall and pay their cancellation fee if they move into the chapter house before the contract is expired. The date to cancel a dorm contract and not be penalized is Aug 31th 2012. Most freshmen do live in the dorms their first year.
When broken down by month, living in a fraternity will be the same price or cheaer than living in an off campus appartment even with chapter dues included. Living in a fraternity house is a once in a lifetime experience and can lead to lifelong connections and friendships.
School Related Expenses
Because of the size of fraternities relative to other student organizations, there is almost always at least one member in your major. Often you will be able to share books or borrow books from members who already took your classes. Your brothers will be very supportive of your academics and will be availible for tutoring. The more help you get, the better you will do in classes. This will reduce the number of classes that will need to be retaken and therefor save money over time.