Where can i get a detailed reality check?

Im going off to college soon and I really really want an apartment (not rent, buy) obviously im not gona get an income by being a doctor or a lawyer because ill be in college so im facing working where a teenager is expected to work but I don't want to live in a charming apartment and be able to pay all the extras like car, clothes, food,and then home stuff, so I want to know more about how much money is reasonable that id need so I looked at reality checks but I can't find a good one...help