help on buying passes to the parks

[katherinecburk]

My husband and I (in our 50's) will be traveling to DisneyWorld for the first time. We will be staying at a condo, so we do not need a package deal that includes passes to the parks, so we are just buying passes.
We are thinking we would like to see Epcot, Animal Kingdom and MK, for 3 days.
What do people recommend? What is the best way to buy these tickets?