You are not a “match” for UNC-Chapel Hill. By law, Carolina has a limit of 18% for non-resident enrollment in each first-year application class. Further, over the past few years the number of OOS applicants have comprised about 2/3 of the total first-year applicants to Carolina; and the acceptance rate for those OOS applicants has been in the single digits, so as to maintain the 18% limit on OOS enrollees for each incoming first-year class. And of those accepted OOS applicants, a good number of them are legacy applicants (i.e., they had a parent who is a UNC-CH alum). Also, you are also very unlikely, as an OOS applicant, to get any financial aid or scholarships from UNC-CH, unless you can get one of the highly competitive Morehead-Cain or Robertson scholarships, which are done through private foundations.
As for BU and USC, you may want to look at the Common Data Set for each of those schools in Sections C9-C11 to see how you compare to matriculated students at each of those schools, and whether these schools might be a “match” for you.
How much annually do you think your family can spend on your education abroad? You might want to think about applying to some public universities in the U.S… Here are some that offer scholarships to international applicants:
Temple University: Scholarships for International Students | Temple University Office of Undergraduate Admissions
Southern Illinois University - Edwardsville: Financial Aid - Scholarships, Awards and Grants | SIUE
Western Illinois University: Presidential Scholarship - Western Illinois University
Southeastern Louisiana University: New Freshman Scholarships
Missouri State University: International Costs - International Services - Missouri State University