you will find that it is cheaper to just go ahead and order even a small quantity. For example, at Rodent Pro, you could order 100 hoppers for $30. It would probably cost you $40 to ship them so you end up paying $0.70 per fuzzy. I suspect that is less than you are paying now. Towards the end of those, your snake might be eating 3 at a time, but the saved expense per fuzzy combined with the saved expense for gas to travel to the pet store once per week would probably end up cheaper.
You could also order 100 hoppers for about the same amount of money. In an order of hoppers you will find some that are as small as fuzzies (7-8 g) while others are almost twice this size (12g). You could, by selecting the correct size each week, work your way through a bag of hoppers as your snake grows.
The real savings come in if you can find someone who wants to order some mice with you, thus splitting the shipping cost in half or more. Is there a herp society in Bloomington? Surely in a University town you can find a like minded person.
Check out RodentPro.com. Their prices are usually about as cheap as you can get and they have great service in my experience. They also vacuum pack rodents so they last longer in the freezer.
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Chris Harrison