This guide provides essential insights and metrics for building a billion-dollar SaaS company, focusing on key terms like cash flow, MRR/ARR, CAC, LTV, and customer churn. To achieve a billion-dollar valuation, companies typically need over $100 million in annual revenue, which may come from various customer bases depending on revenue models. Strategies for sustaining growth include improving customer acquisition and retention, optimizing the lead-to-conversion ratio, and ensuring a replicable business model.