Halloween Haunt

For this event, unfortunately you need to set goals as you won't be able to obtain all of them. Candy corns can be acquired via events at home and in Downtown (and by doing Trick or Treat! quest). Home for Halloween and Costume Construction have 6 hours of cool down, while Halloween Haunt in Downtown has 14 hours of cool down. So make sure to strategize!

I'd suggest you spend the balance candy corns on Creepy Coffins, which you can do much later after you get all the items you want.

Candy corns can also be collected from bowl (should be inside inventory after completing part 2 of Trick or Treat! quest and you can place it at home) and a cauldron which can be purchased from featured store, Halloween Bonus Bundle (it has larger capacity). Both of these get full in 12 hours. You can also collect them earlier before they get full in case you're going to be offline for very long.