What are the essential must haves for owning a cat?

i'm getting a cat from an animal shelter that wil already be nurtured at the end of the summer and i'm trying to figure out all that i need to get for him, it will be an indoor cat only, most likely short haired, and i want a male kitty. what supplies do i need to get if this is my first kitty? i know litter box, food dishes, toys, and food obviously but what else is good? and around how much is each?