@GlitterStar100 It is optional. The $100 deposit is not necessary if you get accepted. As I said in a previous post, the $100 would be transferred to your CMU card to be able to purchase books from the bookstore and do other things at CMU, so all you would be doing is sending in $100 now to use when you get on campus in July. If this is not feasible, shoot them an email after you get accepted and let them know and they will waive the deposit. It is also assumed that you will bring spending money to purchase things around campus and Pittsburgh. If you bring spending money, you will have the ability to transfer some of that money onto your CMU card once you get there.
For accepted students, I’d recommend bringing $200 - $400 for emergency funds, shopping, and the loads of birthday dinners you’ll be attending at multiple restaurants in Pittsburgh. I survived on $300 with $50 left to spare by the end of it. Also, don’t worry about purchasing textbooks. You can easily download them for free online, if you know where to look 
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