Twelve foundational business models power lead generation, from brokers to publishers to technology platforms. Cutting through pitch deck projections reveals operational reality—gross margins masquerade as net margins while brutal cash flow realities stay conveniently hidden. The lead broker model exposes three silent margin killers: returns eating 8-15% of gross revenue, bad debt consuming 1-3%, and float costs from payment timing mismatches requiring $800,000 to $1 million in working capital. Failure comes from running out of capital, not customers. Quality disputes, supplier management, and forensic reconciliation define profitability in this high-stakes industry.