If you are staying ONsite then there is no worries with overcrowded actually.....you are "somehow" in the count.....
The park hopper option is flat rate, so IF you are gonna use it, get it early rather than late in your visit....you CAN always add it....
We LOVE the hopper, but we're a family that will go thru 3 parks in a day to hit all our favs and then run around like crazy (not the dh though) ....there are certain parks we spend ALL day at (MK, my FAV!) BUT we always book out of HS and AK for some reason......
so, figure out your "style" of travel.
Have a great trip whatever you decide!
And yes, you can return, be sure to follow rules (is it still a hand stamp??

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