When it comes to college these days, students are more concerned about how they will pay the tab than they are about getting in, according to a recent survey of college-bound students and their families.Higher education already costs more than most families can afford, and college costs are still rising. Tuition and fees plus room and board for a four-year private college averaged $53,430 in the 2022-2023 school year; at four-year, in-state public colleges, it was $23,250, according to the College Board.For most students and their families, which college they will choose hinges on the amount of financial aid offered, which is laid out in each school’s financial aid award letter.More from Personal Finance:College hopefuls have a new ultimate dream schoolThe cheapest states for in-state college tuitionCollege is still worth it, research findsUnderstanding the college financial aid letterOne of the first things to understand when assessing aid letters is the formula colleges use to come up with the expected family contribution.”It’s not so much what you can afford to pay but what you can afford to finance,” said Kalman Chany, a financial aid consultant and author of The Princeton Review’s “Paying for College.”Chany advises families to wait until all of the offers are in and then compare. What may look like the largest offer might not be the best, he said.”One school might give you $5,000 more grant aid but their cost could be $8,000 more.”It’s not so much what you can afford to pay but what you can afford to finance.Kalman Chanyfinancial aid consultantFurther, not all colleges include both direct and indirect expenses in the total “cost of attendance.”While most schools outline baseline tuition and fees and room and board, some might not include “indirect expenses” such as textbooks, supplies, transportation and any other extras. For each school, list out all the costs, including personal expenses, before deducting grants or scholarships.As a rule of thumb, add an extra $4,000 for those indirect costs if they are not included in the aid offer, Chany said.”You have to look at the net net,” he said.Differentiate free vs. borrowed moneyIn most award letters, there are often several financial aid options, including grants, scholarships, work-study opportunities and student loans.If you’re having trouble telling the difference between gift aid and loans that will need to be repaid, look for terms such as “grant,” “scholarship” and “fellowship.” Anything else is most likely a loan.If student loans are listed, they will appear to reduce the total cost of attendance. But the reality is that loans always need to be repaid — plus interest.Douglas Sacha | Moment | Getty ImagesEven with gift aid, there may be strings attached, such as whether a grant is renewable for all four years or a minimum grade point average that must be maintained. A school that seems more generous initially might also offer less funding down the road, Chany said.In the end, schools will often offer more financial aid than you may need, particularly in loans.As a general rule, don’t borrow any more than you absolutely have to, most experts say. Many people make the mistake of borrowing too much and struggle with repayment down the road.It’s not too late to get more college aidEven if you didn’t apply for financial aid, “it’s not too late,” said Mary Jo Terry, a managing partner at Yrefy, a private student loan refinancing company.In ordinary years, high school graduates miss out on billions in federal grants because they don’t fill out the Free Application for Federal Student Aid, or FAFSA. Many families mistakenly assume they won’t qualify and don’t even bother to apply.As of early March, only 42.7% of the high school class of 2023 had completed the FAFSA, according to the National College Attainment Network. The FAFSA season for the 2023-24 academic year opened Oct. 1, but students who haven’t filed can still apply.For families who have already filed the FAFSA but are still concerned about making ends meet, it is also possible to amend their FAFSA form or ask the college financial aid office for more aid, particularly if you’ve experienced a change in your financial situation, such as a job loss or a disability, Chany said.Financial aid is determined by income information that is not necessarily up to date. For instance, aid for the 2023-24 academic year is based on 2021 income.If your circumstances are now different, that should be brought to the financial aid office’s attention with documentation.Prepare a response with documentation showing any changes in assets, income, benefits or expenses. If the financial aid package from another comparable school was better, that is also worth documenting in an appeal.”Syrupy” letters aren’t as effective as taking a more quantitative approach, Chany advised.”This is a business transaction,” he said. “They are trying to meet their enrollment goals and maintain revenue.”To that end, “play hard to get,” he added. Don’t post wearing the school sweatshirt on social media or make any moves to give the indication that you will enroll anyway.Colleges are likely receptive to appeals, Chany said, but “it’s not a buyers’ market like it was at the onset of the pandemic.”Supplement with private scholarshipsIn the meantime, tap alternative sources for merit-based aid, Terry advised. “There is so much money out there that people don’t even know is available.”There are more than 1.7 million private scholarships and fellowships available, often funded by foundations, corporations and other independent organizations, with a total value of more than $7.4 billion, according to higher education expert Mark Kantrowitz.”Every 40 hours you spend applying for scholarships and grants will result in $10,000, on average,” Yrefy’s Terry has calculated.Check with the college, or ask your high school counselor about opportunities. You can also search websites such as Scholarships.com and the College Board.Subscribe to CNBC on YouTube.