In the top tier US universities, if you get admitted, these universities will meet 100% of your financial needs because they follow the need blind and need aware admissions - that's, if you don't even have a one dollar to pay, they will take it into consideration and will not take it against you. So if you get in, they will award you full ride scholarships in the forms of grants, bursaries, on campus work, and assistantship. The hardest part here is that how you can get admitted to these prestigious universities with an acceptance rate of 5% - 50% for international students!!??? And how you can fulfill their requirements? These are the hardest questions that need to be answered!
Good Luck!