What Is Scenario Planning?
Scenario planning builds distinct cases: base (your best estimate), upside (rent 5% higher, vacancy 2% lower), downside (rent 5% lower, vacancy 12%). You see the range of cash-flow and cash-on-cash-return. It complements sensitivity-analysis—sensitivity varies one input; scenarios combine multiple inputs into coherent stories. Use it for go-no-go-decision: if the downside is acceptable, the deal may be worth it. If the downside is ugly, pass.
Scenario planning is the process of modeling multiple distinct outcomes for a deal—such as base case, upside, and downside—to understand the range of possible results and inform the investment decision.
At a Glance
- What it is: Model base, upside, downside (or more) cases
- Why it matters: See range of outcomes; inform decision
- Typical cases: Base, upside, downside
- Differs from sensitivity: Combines inputs into coherent scenarios
- Use it for: Deal-analysis, go-no-go-decision
How It Works
Base case. Your best estimate—market-rent from rental-comps, 8% vacancy, 42% expense ratio. This is your "expected" outcome.
Upside case. Rent 5% higher (you capture below-market-rent faster). Vacancy 5%. Expenses 38%. What's cash-flow and cash-on-cash-return? Optimistic but plausible.
Downside case. Rent 5% lower. Vacancy 12%. Expenses 46%. Rate 0.5% higher. What happens? If cash-flow goes deeply negative, the deal is fragile.
Decision rule. Some investors require the downside to still be positive cash-flow or at least break-even. Others accept negative in downside if base and upside are strong. Define your rule.
Value-add. For brrrr or value-add, scenarios might include: on-time/on-budget, 3-month delay, 15% rehab overrun. Each changes arv and refinance outcome.
Real-World Example
Ava in Indianapolis. Ava built three scenarios for a 6-unit. Base: $4,200 gross, 8% vacancy, 42% expenses. Cash-on-cash-return: 6.2%. Upside: $4,400 gross, 6% vacancy, 40% expenses. CoC: 8.1%. Downside: $4,000 gross, 12% vacancy, 45% expenses. CoC: 2.8%. Downside was still positive. She bought. Year one was between base and upside—7.1% CoC. The scenario range had prepared her for variance.
Pros & Cons
- See full range of outcomes
- Informs go-no-go-decision
- Complements sensitivity-analysis
- Conservative-underwriting when downside is realistic
- Can overcomplicate
- Scenarios are still estimates
Watch Out
- Upside bias: Don't make upside too rosy
- Downside realism: Downside should be plausible—not apocalyptic
Ask an Investor
The Takeaway
Scenario planning models base, upside, and downside. Use it with sensitivity-analysis to stress-test deals. If the downside is acceptable, you can proceed with eyes open.