Disney does not offer different rates for length of stay. There are of course different rates depending on the time of year. Jan 1 to Feb 15 is the lower rate time. This year we are participating in a group called "Loop Group". The organizer collects commitments from a group of people and then with those in hand negotiates with Disney for a reduced rate. There is a fee to join the group but overall you save money for a long term stay. It is an annual thing and so closed for 2014 but will probably operate in coming years unless Disney decides it is no longer profitable.