Original calculations · documented assumptions · practical takeaways
Our Worked Financial Cases turn abstract finance advice into a clear sequence of numbers, decisions and trade-offs. Every case explains its assumptions, shows the arithmetic and links to a matching tool and worksheet. All cases currently in this library are transparently fictional models—not interviews or reports of actual customers.
Explore the three original worked cases
Photo: Kaboompics / Pexels · freely licensed stock image
Freelancer cash flow
$1,400 cash gap
When a $4,800 invoice arrives after two bill cycles
See how accessible cash, bills and a planned tax reserve create a shortage before the invoice is actually paid—and how to model earlier collection.
Photo: Tima Miroshnichenko / Pexels · freely licensed stock image
Borrowing decisions
$527.61 extra cost
A smaller payment does not mean a cheaper loan
Compare 24 and 36 months for the same $8,000 borrowed at an assumed nominal rate; see what changes and what the model excludes.
Photo: Polina Zimmerman / Pexels · freely licensed stock image
Student financial aid
$2,000 net-price difference
Higher sticker price, lower net price
Follow two fictional aid packages, separate grants from loans and work-study, and calculate the real gift-aid difference.
Our case-study standard
1. Starting assumptions
We disclose the starting balances, periods, fees and other input values before drawing conclusions. Fictional values are labeled rather than attributed to unverified people.
2. Arithmetic that can be checked
Each case provides sufficient detail to recalculate the outcome, including what is and is not subtracted from cash, a cost estimate or net price.
3. A decision, not only a number
We explain what the result means, what it does not prove, and the questions to ask before applying it to a real situation.
4. Related primary sources
Where regulations or program definitions matter, we link directly to official sources. Example inputs are not falsely presented as government statistics.
Apply the method to your own numbers
Use the Financial Decision Lab for interactive loan-payment sensitivity. Visit Tools & Calculators for specific invoice, tax reserve, college aid and payment-security tools. Download editable planning files from the Free Finance Worksheets Library. For evidence about aggregate credit trends rather than personal cases, explore our Research & Data Center.
Can a fictional model be useful evidence?
A transparently specified model provides evidence about the consequences of its assumptions, not evidence that a named household, company or student had that experience. The value is reproducible reasoning. Observational claims about U.S. households, lenders or students would require separate real datasets, verifiable documents or interviews with consent. The current examples do not claim that kind of primary reporting.
We welcome corrections to calculations and source links through our Corrections Policy. Our Editorial Policy explains publication responsibility. No third-party expert review or borrower testimonials are claimed for this library.
Start with one interactive model, check the related worked case, and take the corresponding spreadsheet template into your own planning process.
Use each case as a decision exercise
These three scenarios are explicitly fictional. They help test reasoning under stated assumptions; they are not customer experiences, lender offers, student aid awards or population averages. The most useful step is to change one input, recalculate and identify which decision would actually change.
1. Freelancer invoice timing: distinguish a receivable from cash
The case begins with $4,200 accessible cash and two months of modeled obligations totaling $5,600. Before collection, the gap is $1,400. An early cleared partial receipt of $1,400 would cover that modeled gap exactly, but leaves no safety buffer. To keep a separate $500 buffer under the same assumptions, the business would need $1,900 available before the second obligation cycle—about 39.58% of the $4,800 receivable. A promised payment cannot be counted until it is usable cash. Try an additional expense or slower collection date in the invoice delay calculator.
2. Loan term: a lower installment has a lifetime cost
For a fictional $8,000 fixed-rate loan at 12% nominal interest and a separately paid $150 fee, the 24-month schedule is about $376.59/month and $9,188.11 all-in. A 36-month schedule is about $265.71/month but $9,715.72 all-in. Someone with a $300 payment limit might reject the first model on cash-flow grounds, but the second would cost approximately $527.61 more if paid exactly as scheduled. Whether either real offer is suitable still depends on disclosed APR, net cash received, repayment terms and budget stability. Reproduce both schedules in the Decision Lab.
3. College aid: check gift-aid renewal before comparing years
In the fictional aid case, School A costs $29,000 and offers $18,000 in grants, giving an $11,000 modeled annual net price. School B costs $22,000 with $9,000 in grants, giving a $13,000 net price. If A’s gift aid falls by $4,000 the next year while other assumed amounts stay unchanged, A rises to $15,000 and the modeled price advantage switches to B by $2,000. This is a sensitivity test, not a prediction of scholarship renewal. Verify the actual written conditions and the same academic-year costs using the aid comparator.
A four-question checklist before you apply any example
- Are the amounts from your real contract, invoice, loan disclosure or aid letter—and are they for the same period?
- Which entries represent cleared cash or nonrepayable aid, and which are future receipts, debt or possible earnings?
- What changes if one expected payment, interest rate, cost or scholarship is different?
- What is the next reversible action: verify terms, request documentation, test the timing, or seek qualified advice when appropriate?
Keep fictional assumptions clearly labeled in any notes you share. For official definitions consult Federal Student Aid’s aid-type guide and the CFPB’s APR explanation. No independent expert review or real borrower/college outcome is implied by these examples.