Case Studies
Example household scenarios and what moves the Kill Line the most.
These case studies are intentionally simplified. They exist to show how the model behaves and where leverage points typically are.
Case 1: High income, thin buffer
Profile:
- Income: $140,000
- Liquid assets: $8,000
- Fixed costs: $6,500 / month
- Debt payments: $900 / month
What tends to happen:
- The household can look “fine” on paper, but the runway is short.
- A job shock quickly turns into missed payments because fixed costs dominate.
Open in calculator:
/calculator?income=140000&assets=8000&fixed=6500&debt=900&scenario=unemployment&unemployment_months=4
Case 2: Moderate income, stable fixed costs
Profile:
- Income: $78,000
- Liquid assets: $18,000
- Fixed costs: $3,200 / month
- Debt payments: $250 / month
What tends to happen:
- Runway can be surprisingly decent because fixed costs are controlled and buffer exists.
Open in calculator:
/calculator?income=78000&assets=18000&fixed=3200&debt=250&scenario=combo
Case 3: Rent shock
Profile:
- Income: $95,000
- Liquid assets: $12,000
- Fixed costs: $4,300 / month
- Debt payments: $450 / month
- Rent shock: +25% for 8 months
Open in calculator:
/calculator?income=95000&assets=12000&fixed=4300&debt=450&scenario=rent&rent_increase_pct=25&rent_shock_months=8
How to use case studies
If your result looks “bad”, don’t panic. Use the calculator to test changes:
- reduce fixed costs by 5–10%
- reduce debt service
- increase buffer by one month of essentials
The biggest gains often come from small, boring changes repeated over time.
Disclaimer
These are educational examples and not advice.