Tip from a 2013 July bride...If you are planning to have a candy buffet now is the time to buy you candy - when Halloween candy goes on sale for half off or more!!
It will keep for several months (some candy keeps for years) - check for expiration dates.
Be careful not to buy candy that has Halloween wrappers on it.
I did this last year for my July wedding and everything still tasted fresh and I saved a TON!
Be careful with Reese Cups, they tend to go back the quickest.
Avoid the mixed bags as they will "trade flavors" amongst the candy over time.
People will prefer "premium" individually wrapped candy to the color specific loose candy. If you buy now you can afford to offer the good stuff and not have to buy bulk yucky stuff :-9
Good luck!