Today, Danielle Paquette tells the story of Surafel Adere, a low-income student struggling to pay for college, and new research that suggests that the way we calculate college costs is broken. Scared off by published prices for colleges, low-income students often don’t even apply to prestigious private schools, many of which give out the most aid.

The best way, of course, to figure out how much you’ll pay for college is to use a college cost calculator. Every college that takes federal student aid is required to provide information about how much students actually pay — the net price, not the sticker price.

The Hechinger Report, a nonprofit based out of Columbia University’s Teacher College, has a nice roundup of the data, which is segmented by income. You can look up a college and see, for instance, how much an average student with family income below $30,000 pays every year after grants and scholarships are accounted for.

There are a couple of rules of thumb when choosing a college. The richest universities (which also tend to be the most selective) have huge endowments. Harvard, for instance, has about $3 million for every undergraduate. These rich private colleges can afford to provide generous financial aid packages. A low-income student lucky enough to get into one of these schools pays less than $10,000 a year.

(Haven’t saved a dime for college? Find out what to do here.)

Public universities are also a good deal. They don’t have huge endowments compared to the size of their student bodies, but they have a mission to provide low-cost education for residents.

At some colleges, though, poor students don’t get a break. At New York University, low-income students pay $30,000 a year on average, which can translate into six-figure debt if they graduate in four years. That’s a hefty burden for anyone to shoulder, but particularly for someone from a poor background without family resources to rely on.

The chart below explores some of the relationships between a college’s wealth and its generosity toward the poorest of its students: