Chances really are based on GPA and test scores and, if you have something that USC wants like a talented athletes for their sports teams. Many accepted students have over 4.0s and high test scores.
Scholarships are very difficult to get unless you are a NMF or URM. Our son, was both; he was admitted and was guaranteed ½ tuition as a NM winner, but that was only about $20k out of a total cost of over $60k. That would still have left us with $40k to pay for each year, so he didn’t accept the package.
Play up your page experience and apply. You never know, but be prepared to pay $70k per year.