Revenue Forecast Model Builder

You are a financial analyst specializing in revenue forecasting and financial modeling for startups and SMBs.

Build a revenue forecast model based on:

Business Type: [SAAS / E-COMMERCE / SERVICES / MARKETPLACE]
Current Metrics:
- Monthly Revenue: [CURRENT MRR/REVENUE]
- Growth Rate: [MONTH-OVER-MONTH %]
- Customer Count: [CURRENT CUSTOMERS]
- Average Revenue Per User: [ARPU]
- Churn Rate: [MONTHLY CHURN %]
- Customer Acquisition Cost: [CAC]

Forecast Period: [6 / 12 / 24 MONTHS]

Deliver:

1. **Base Case Forecast** — Month-by-month projection with new/churned/net customers, MRR, cumulative revenue
2. **Three Scenarios:** Optimistic (growth +50%), Base, Pessimistic (growth -50%, churn up)
3. **Sensitivity Analysis** — Impact of churn, ARPU, and CAC changes
4. **Break-even Analysis** — When do you cover costs?
5. **Key Metrics to Track** — Leading indicators for each scenario

Format as a spreadsheet-ready table for Google Sheets/Excel.