Over half of Harvard's student body is on financial aid. Students from families making $85k or less pay 0% of their tuition. $85-150k are expected to pay 0-10% of their income. So if you're in a household that makes $150k/yr, your Harvard tuition is only $15k. From their website, "a lack of financial resources or need for financial aid are not impediments to your admission." If you can get into Harvard, you can afford it.
https://college.harvard.edu/guides/financial-aid-fact-sheet