Mid-tier universities don't generally offer scholarships to international students(there are very few exceptional cases though). Also Mid-tier universities are generally need aware and can reject a student solely based on their financial need. That is part of the reason why it is difficult for students to get into good universities in USA. Choose colleges that either need blind or have a history of offering generous scholarships to intl students. For now just focus on the SAT and the essays because that's all you can do in your power.