This guide treats the purchase and sale of a privately held business systematically. Part one covers deal structures — asset purchase, equity purchase, and merger — and the tax consequences that drive the choice, including purchase price allocation, section 338 elections, reorganizations, and the qualified small business stock exclusion. Part two covers valuation: the three approaches, the earnings adjustments that determine price, the discounts that reflect concentration and owner dependence, and the devices that bridge disagreement about the future. Part three is a complete due diligence framework across financial, legal, human resources, operational, environmental, and regulatory categories, with the findings that should end a deal. Part four covers the transaction documents from the letter of intent through the purchase agreement, with detailed treatment of representations, disclosure schedules, indemnification architecture, and escrow. Part five covers the mechanics that determine whether a deal closes on time — working capital adjustments, employees and WARN notice, landlord and lender consents, licenses, antitrust notification, and tax clearance. Part six covers successor liability doctrines. Part seven covers post-closing disputes. Worked examples appear throughout.