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:
- Will this hire directly contribute to revenue?
- What's the time-to-productivity? (Factor into ROI)
- What else could this salary fund?
- 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 for detailed metric calculations and industry benchmarks
- See references/case-studies.md for examples from Mailchimp, Zapier, Basecamp, ConvertKit, and Zoho