USC is my dream school. I have been wanting to attend for the longest time, but I just couldn’t get my GPA and SAT scores up. Along with that, it is way too expensive and there’s not enough financial aid in the world to make it affordable. I’m still hanging onto the slightest ounce of hope but I think at this point I’ve just got to accept that I’ll never be able to attend. But, if I wanted to transfer in after a semester, could I potentially get a lot of financial aid?
USC does promise to meet 100% of a student’s need-based costs, but that will often include loans. For me, USC met all of my tuition-related expenses, but did not cover room/board. Also, as I was uninsured, I did need to take out some loans to pay for the student insurance. I live about 8 miles away from USC, so rather than take out loans just to live on-campus, I chose to commute.
In short, USC can very well cover all of your educational-related expenses depending on your parent’s income. However, if they make too much, they will offer loans that cover the remaining cost (such as the Parent PLUS loan that allows your parents to borrow whatever is needed - up to the cost of attendance). I’ve rarely, if ever, seen USC cover housing expenses with financial aid.
“Scholarships awarded may only be used to replace University tuition costs and may not be used to cover housing, books, fees, or meal plans.”
^This is from a scholarship page on the Dornsife site, so it seems like scholarships almost never help with housing expenses either. USC can definitely take care of the staggering tuition for transfers 
but it just seems like you will have to carry the burden of housing expenses should you choose to live on-campus.
My parents have a high EFC, so even if they meet 100% need based on that, it will still be too much. Would already being in college for a semester or two lower my EFC?
No to the above question. Your EFC is based on your parents income so if it is high, then your EFC will remain high. Run the Net price calculator to see your cost estimate.
https://financialaid.usc.edu/undergraduates/prospective/net-price-calculator.html
“Meets need” in the college world means meets their definition of need, not necessarily yours. If your parents can’t or won’t meet your EFC (as calculated by a given college), it is likely unaffordable.
The financial aid calculator posted by Gumbymom is incredibly accurate. It was almost spot on in terms of the gift aid that I was going to receive. It will give you a clear picture about what your parents will be expected to contribute.