For USA universities, once you get the admission the university will ask you to provide the financial statement in order to issue I-20. That will be sufficient to show for getting I-20. However, during visa application process, the interviewer may want more money in the bank. So to be on the safe side, please show as much as possible.
Regarding the cost, it varies from state to state. In some states, tuition fee and living cost are lower compared to NY/NJ states. If you want to pursue on self-pay, please consider Tuition fee, living cost, and public transport. And you can email to graduate coordinator to give you an estimate for the cost.