How much ice cream should I purchase for a party of 27 people?

ice cream toppings image

Annie

I'm throwing an ice cream party, and I need to purchase ice cream and toppings for a group of 27 people. For toppings, I'm buying carmel syrup, chocolate syrup, chocolate chips, whipped cream, sprinkles, whipped cream and cherries. If you have any suggestions for ice cream flavors or other toppings, please let me know! Thanks :)
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Thanks for all your great advice! I actually went with a snack size Häagen-Daz, which I purchased from Costco, a local discount retailer and warehouse club. It was cheap and exact; everyone got the same amount :)

Answer
200 gallons minimum and that's just Vanilla