Is the investment multi-year?
  YES → Use NPV (+ IRR to compare alternatives)
  NO  → ROI is sufficient

Is this a build vs. buy decision?
  YES → TCO comparison across all three options
  NO  → Skip TCO, use NPV/ROI

Are assumptions uncertain?
  YES → Add sensitivity analysis (3 scenarios)
  NO  → Base case only

ROI = (Net Benefits - Total Costs) / Total Costs × 100%

NPV = Sum(Cash Flow_t / (1 + r)^t) - Initial Investment
  r = discount rate (10% enterprise, 15-20% growth, 25-40% startup)
  Decision: Accept if NPV > 0

IRR = discount rate where NPV = 0
  Decision: Accept if IRR > hurdle rate

Payback Period = Initial Investment / Annual Cash Flow
  Benchmarks: SaaS 6-12 mo, Enterprise platform 12-24 mo, Infra 24-36 mo

TCO = CAPEX + (OPEX × years) + Opportunity Cost + Hidden Costs

# Business Case: [Project Name]

## Executive Summary
[2-3 sentences: what we're investing in and expected return]

## Financial Analysis

### Investment Required
| Item | One-Time | Annual |
|------|----------|--------|
| Development | $X | |
| License / SaaS | | $X |
| Implementation | $X | |
| Training | $X | |
| Maintenance | | $X |
| **Total** | **$X** | **$X** |

### Expected Benefits
| Benefit | Annual Value | Confidence |
|---------|--------------|------------|
| Time savings (X hrs × $Y/hr) | $X | High |
| Error reduction | $X | Medium |
| Revenue uplift | $X | Low |
| **Total** | **$X** | |

### Key Metrics
| Metric | Value |
|--------|-------|
| 3-Year TCO | $X |
| NPV (10% discount) | $X |
| IRR | X% |
| Payback Period | X months |
| ROI | X% |

## Sensitivity Analysis
| Scenario | Discount Rate | Year 1 Benefits | NPV |
|----------|---------------|-----------------|-----|
| Base case | 10% | $X | $X |
| Conservative | 15% | $X × 0.75 | $X |
| Optimistic | 8% | $X × 1.25 | $X |

## Risk Analysis
| Risk | Probability | Impact | Mitigation |
|------|-------------|--------|------------|
| | | | |

## Recommendation
[GO / NO-GO] — [one-sentence rationale]