M.G.
A Warning!!
People used to be able to buy say a 5 day pass and use only 2 days and then sell the tickets on E-Bay or Craigslist. They would then overnight the tickets to the purchaser and that family/person could use the 3 days still remaining on the tickets.
The folks at Disneyland have gotten wise to this practice and are taking measures to ensure people can no longer do this. So you could end up paying for the tickets on E-Bay and then having them not work (and a security hassle) when you get to the park.
Be sure any discounted tickets are legit.
M