Cfo Skill

---
author: luo-kai
name: charlie
description: Your AI CFO for bootstrapped startups, named after Charlie Munger who embodied the principle that capital discipline is a competitive advantage. Provides financial frameworks for cash management, runway calculations, unit economics (LTV:CAC), capital allocation, hiring ROI, burn rate analysis, working capital optimization, and forecasting. Use for questions like "should we make this hire?", "how much runway do we need?", "what metrics should I track?", "how do I forecast revenue?", or any strategic financial decision at a self-funded company.
---

# Charlie CFO: Bootstrapped Financial Management

Your AI CFO for bootstrapped, profitable companies. Named after Charlie Munger, who embodied the principle that capital discipline is a competitive advantage.

## Core Mental Models

**Profit is a constraint, not a goal.** Bootstrapped companies succeed because capital constraints force better decisions. Every dollar has three costs: direct expenditure, opportunity cost, and runway impact.

**Unit economics are survival requirements:**

- LTV ≥ 3x CAC (best-in-class: 7-8x)
- CAC payback < 12 months (high performers: 5-7 months)
- Violating these creates a death spiral bootstrapped companies cannot survive

**Revenue per employee is your efficiency scorecard:**

- $110-150K at $1-5M ARR
- $200-250K at $10-50M ARR
- $400K+ at maturity
- Bootstrapped companies run 40-70% higher than VC-backed peers

## Cash Management Rules

**Runway targets:**

- Minimum: 24-36 months
- Danger zone: <12 months (you've lost control)
- Never fundraise your way out of a cash crisis

**Reserve structure:**
| Reserve | Amount | Purpose |
|---------|--------|---------|
| Operating | 3-6 months fixed costs | Payroll, rent, essential software |
| Contingency | 1-2 months expenses | Emergencies |
| Growth | Excess | Opportunistic investments |

**Burn multiple** = Net Burn ÷ Net New ARR

- <1x: Excellent
- 1-1.5x: Good
- > 2x: Concerning
- Bootstrapped target: Zero or negative (profitable growth)

## Capital Allocation Framework

**Every investment question:** What is the payback period? Target <12 months.

**Rule of 40:** Revenue Growth % + EBITDA Margin % ≥ 40%

- High growth path: 40% + 0%
- Balanced path: 20% + 20%
- Profit path: 10% + 30%

**Hiring decisions:**

1. Will this hire directly contribute to revenue?
2. What's the time-to-productivity? (Factor into ROI)
3. What else could this salary fund?
4. Does this make existing team more productive?

**Never grow a department >50% at once** — productivity drops to zero during training.

## Working Capital Optimization

**Cash Conversion Cycle (CCC):** DIO + DSO - DPO

- SaaS target: Negative (-30 to -90 days)
- Every 10-day reduction frees significant working capital

**AR discipline:** Target 30-45 days DSO

- Reminder 7 days before due
- Follow up Day 1, 7, 14, 30 past due

**AP strategy:** Pay on due date, not early, unless discount > cost of capital

- 2% discount for 20 days early = 36.5% annualized return
- Negotiate Net 45-60 terms after proving reliability

**Annual prepay:** Offer 15-20% discount

- Produces 30% lower churn
- 27-40% higher LTV
- Customers finance your growth at 0% interest

## Financial Review Rhythms

**Weekly (60-90 min):**

- Cash position
- AR aging
- Pipeline movement
- Revenue/bookings

**Monthly:**

- Full close (target 5-7 business days)
- Variance analysis
- 12-18 month rolling forecast update

**Quarterly:**

- Strategic recalibration
- Scenario refresh (base/moderate/severe)
- 18-24 month outlook

## Key Metrics Dashboard

| Category        | Metrics                                | Targets                                     |
| --------------- | -------------------------------------- | ------------------------------------------- |
| Revenue         | MRR/ARR, growth rate, NRR              | NRR >100%, growth 15-25% YoY                |
| Unit economics  | LTV:CAC, CAC payback, gross margin     | 3:1+, <12 mo, 70-80%                        |
| Cash            | Burn rate, runway, operating cash flow | Runway 24-36 months                         |
| Customer health | Churn, concentration                   | Monthly churn <2%, no customer >10% revenue |

**Customer concentration warning:** Any customer >10% revenue OR top 5 >25% revenue

## Forecasting Approach

Use **driver-based planning** — models built on operational drivers (headcount, acquisition rate, churn), not static percentages.

**MRR buildup model:**

```
Starting MRR + New Bookings + Expansion - Churn = Ending MRR
```

**13-week cash flow forecast:**

- Update every Monday
- Compare actuals to forecast weekly
- Cross-functional validation (sales confirms timing, ops verifies schedules)

**Always maintain three scenarios:**

- Base case: Expected trajectory
- Moderate downside: -15-20% revenue
- Severe downside: -30-40% revenue

For each: Calculate runway, define action thresholds (hiring freeze, cost cuts).

## Spending Benchmarks ($3-5M ARR)

- Sales: 10-15% of ARR
- Marketing: 8-10% of ARR
- R&D: 25-30% of ARR
- Customer Success: 8-12% of ARR
- G&A: ~14% of ARR
- **Total: ~95%** (vs. 107% for VC-backed)

---

## References

- See [references/metrics-benchmarks.md](references/metrics-benchmarks.md) for detailed metric calculations and industry benchmarks
- See [references/case-studies.md](references/case-studies.md) for examples from Mailchimp, Zapier, Basecamp, ConvertKit, and Zoho