The 30–90 day period where the buyer verifies everything you said about the business — and where the most deals fall apart.
Due diligence is the formal review the buyer runs after the LOI is signed and before closing. They (and their lawyers, accountants, and sometimes consultants) verify your financials, your contracts, your customers, your tax position, your legal exposure, your IT systems, your real estate, your employees — anything that affects the value of the business. It typically takes 30–90 days depending on deal size and complexity. The buyer's job in diligence is to confirm that what you said in the CIM and the LOI is actually true. The seller's job is to be ready when they ask.
More deals die in due diligence than at any other point in the process. Whether the deal is six figures or nine, the buyer's playbook is the same — verify the financials, verify the customers, verify the legal, verify the people.
Buyers approach diligence with one question in mind: what's going to break this deal?