Irregular Commission Income and a Premature Home Purchase
Marcus and Elena have two children, ages 6 and 3. Marcus is a sales manager with a $78,000 base salary plus commissions that ranged from $0 to $46,000 over the last three years; Elena earns $24,000 part time. Fixed obligations include $2,350 rent, $1,450 daycare, $780 combined car payments at 8.9%, a $410 minimum student-loan payment on $41,000 at 5.5%, and $520 minimum credit card payments on $19,000 at 24%. They have $3,200 in savings and no emergency fund. In low-commission months they use the credit card for groceries and utilities, then pay it down after a strong quarter. They want to buy a $420,000 house in 18 months and ask whether they should pause retirement contributions to save a down payment. Their 401(k) balances are $96,000; Marcus contributes 6% and receives a 3% employer match.
1. Build an annualized cash-flow baseline that reflects income volatility, and show why an average-commission budget would mislead this household. What stress test should they use?
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Annualized fixed obligations are rent $28,200, daycare $17,400, car payments $9,360, student loan $4,920, and card minimums $6,240-$66,120 before food, utilities, insurance, taxes, and maintenance. If normal living costs are $3,000 per month ($36,000), the household needs about $102,000 after tax just to stand still. Base salary plus Elena's pay is $102,000 gross, so even before commissions there is a shortfall after tax; commissions are not surplus, they are required for ordinary life.
An average-commission budget is misleading because commissions ranged from $0 to $46,000. The average may look like a surplus, while a zero-commission quarter produces a cash deficit. The stress test should use the lowest actual three-month commission run rate, not the average, plus a separate 'commission gap' reserve equal to three months of fixed obligations-about $16,500-and a full emergency reserve of three to six months of essential expenses. The test question is: 'Can we pay rent, daycare, cars, minimum debt, food, and utilities for 90 days with zero commission and no new credit-card borrowing?' Until the answer is yes, the household is not stable.
2. Prioritize the competing goals-emergency reserve, 24% credit card debt, 401(k) match, and an 18-month house down payment-and recommend a concrete order of operations with numbers.
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Order of operations: (1) capture the full 3% employer match-it is an immediate 50% return on the 6% contribution and should not be paused; (2) build a $5,000 mini-reserve, about one month of fixed obligations, to stop new card use; (3) attack the 24% card with every commission dollar above the baseline, using a 0% balance transfer only if the card can be closed to new spending; (4) after the card is gone, build the full reserve and increase the student-loan payment; (5) reconsider the house.
The house is the weakest goal. A $420,000 purchase with little down payment, volatile income, $19,000 of card debt, and daycare costs would likely produce a debt-to-income ratio above 43% and leave no reserve. A realistic target is 36 months, not 18, with 10% down plus closing costs and a six-month reserve. If they insist on 18 months, they would have to cut daycare, sell a car, or delay the purchase. I would not pause the 401(k) match to fund a down payment; that trades a guaranteed 50% return for a speculative housing timeline.
3. What behavioral guardrails would you build into the budget to stop the credit-card smoothing cycle?
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Use base salary as the budget ceiling; commission is not spending money until it is allocated. Set automatic transfers on commission paydays: 50% to debt above minimums, 30% to reserve and sinking funds, and 20% to planned irregular expenses. Use separate accounts for bills and variable spending, and a weekly low-balance review. Remove card credentials from online merchants and use a debit card for groceries; keep one card frozen for true emergencies. Pre-commit a rule that any purchase over $200 waits 48 hours. Track the trigger-low-commission months-and have a pre-planned response: pause discretionary spending, not borrow. Review monthly with a one-page cash-flow statement. The goal is to make the cycle visible and make borrowing harder than saving.