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Due diligence is the phase of an M&A transaction where a buyer verifies everything the seller has represented. For founders, it is also the phase where deals are most vulnerable to retrading, delay, and collapse. How you prepare for due diligence—and how your advisor manages it—directly determines whether you close at the price and terms you agreed to.
Due diligence is the formal investigation a buyer conducts after signing a Letter of Intent and before executing the definitive purchase agreement. It is the buyer’s opportunity to confirm that the business is what the seller has represented it to be—financially, legally, operationally, and commercially.
In a typical lower middle market transaction, due diligence runs four to eight weeks. During this period, the buyer and its advisors—accountants, lawyers, and operational consultants—will request and review hundreds of documents, conduct interviews with management, visit facilities, and perform independent verification of the seller’s financial and operational claims.
From the seller’s perspective, due diligence is not a passive exercise. It is a period of intense scrutiny that requires preparation, responsiveness, and discipline. The speed and quality of the seller’s responses directly affect the buyer’s confidence—and, by extension, whether the transaction closes at the agreed-upon terms or gets repriced.
A well-run sell-side process anticipates due diligence from the beginning. The advisor prepares the seller’s documentation, organizes the data room, and manages the flow of information so that the process runs efficiently and confidentiality is maintained throughout.
Due diligence is not a single investigation. It is a coordinated set of workstreams, each examining a different dimension of the business. The scope and intensity of each workstream varies by transaction size, industry, and buyer type—but all six are present in virtually every lower middle market M&A transaction.
The most intensive workstream. The buyer’s accountants will analyze three to five years of historical financial statements, tax returns, monthly revenue detail, and accounts receivable and payable aging. They are looking for revenue quality (recurring vs. one-time), EBITDA normalization adjustments (add-backs, owner compensation, one-time expenses), working capital trends, and the sustainability of the company’s margin profile. In many transactions, the buyer will commission a Quality of Earnings report from an independent accounting firm that independently verifies the seller’s reported EBITDA.
The buyer’s legal counsel will review the company’s corporate structure, articles of incorporation, shareholder agreements, material contracts, employment agreements, intellectual property registrations, pending or threatened litigation, regulatory compliance history, and insurance coverage. Legal diligence identifies risks that could create liability for the buyer post-close—and any issues discovered will inform the representations and warranties in the definitive agreement and, potentially, the indemnification provisions.
How the business actually runs. Buyers will evaluate management team depth, key-person dependency, facility conditions, supply chain relationships, vendor concentration, and process documentation. For founder-led businesses, the central question is transferability: can this business operate at its current level without the founder? The answer to that question directly affects deal structure, transition requirements, and—frequently—the valuation itself.
The buyer’s assessment of the company’s market position, competitive dynamics, customer relationships, and growth prospects. This may include customer reference calls, market sizing analysis, competitive benchmarking, and evaluation of the sales pipeline. Customer concentration—the percentage of revenue attributable to the largest accounts—is a critical focus. A business where a single customer represents 30%+ of revenue will face harder questions than one with a diversified customer base.
For technology companies and businesses with significant IP assets, this workstream evaluates the technology stack, code quality, technical debt, data security practices, patent portfolio, trade secrets, and licensing agreements. Buyers are assessing whether the technology is scalable, defensible, and properly documented. For SaaS companies, this includes infrastructure architecture, uptime history, security certifications, and data handling compliance.
The buyer will review the organizational chart, employment contracts, compensation structure, benefits programs, non-compete agreements, and turnover history. In founder-led businesses, the depth of the management team below the founder is a key concern. Buyers want to understand whether the existing team can execute the business plan post-close and what retention incentives may be required to ensure continuity during the transition period.
In the majority of lower middle market M&A transactions, the buyer will commission a Quality of Earnings (QoE) report from an independent accounting firm. This is the single most consequential diligence deliverable for the seller because it directly determines whether the EBITDA used to price the transaction is confirmed, adjusted upward, or adjusted downward.
The QoE analysis examines the company’s reported earnings in granular detail. It identifies non-recurring items that should be added back (one-time legal expenses, non-recurring consulting fees, personal expenses run through the business), items that have been improperly normalized (above-market owner compensation that exceeds a reasonable replacement cost), and recurring expenses that may have been excluded (deferred maintenance, below-market rent on related-party leases).
The QoE will also analyze revenue quality. Recurring revenue—subscription contracts, retainer arrangements, long-term service agreements—is weighted more favorably than project-based or one-time revenue. Revenue concentration, seasonality, and customer churn are all scrutinized.
For founders, the critical point is this: the QoE is the buyer’s primary tool for confirming or challenging the purchase price. If the QoE identifies material EBITDA adjustments—downward—the buyer will seek a corresponding reduction in price. This is retrading, and it is the most common mechanism through which deals close below the LOI price. Proper preparation, including a sell-side QoE or pre-diligence financial review, is the most effective way to prevent surprises.
Every dollar of EBITDA that disappears during due diligence costs the seller that dollar multiplied by the deal multiple. A $200,000 downward adjustment on a 6x deal is a $1.2 million reduction in enterprise value.
The most effective due diligence preparation begins months before the LOI is signed. Founders who invest in exit readiness before going to market consistently achieve better outcomes than those who scramble to organize information after diligence requests begin arriving.
Retrading—where the buyer reduces the purchase price after the LOI is signed, citing findings from due diligence—is the most significant risk sellers face during this phase. Some retrading is legitimate: if diligence reveals material issues the seller did not disclose, a price adjustment may be warranted. But some retrading is opportunistic, and the distinction matters.
Opportunistic retrading typically occurs when the buyer knows the seller is psychologically and financially committed to closing. By the time a seller has spent months in a process, shared sensitive information, and begun planning for life after the transaction, walking away from a reduced offer is emotionally and practically difficult. Some buyers use this dynamic deliberately, submitting aggressive LOIs to win the competitive process and then using diligence to bring the price down to their actual target.
The best defenses against retrading are structural.
Competitive process. If the seller has maintained contact with backup bidders, the buyer knows that an unreasonable retrade could result in the seller returning to another qualified party. A well-run competitive process preserves this leverage even after exclusivity is granted.
Thorough pre-diligence preparation. If all material issues have been disclosed and addressed before the LOI, the buyer has less basis for a price adjustment. Surprises create leverage for buyers. Transparency eliminates it.
Advisor management of the diligence process. An experienced M&A advisor monitors the buyer’s diligence requests for signs of retrading behavior, manages information flow to prevent scope creep, and intervenes early when the buyer’s advisors begin building a case for a price reduction rather than genuinely investigating the business.
Clean LOI terms. An LOI with well-defined purchase price provisions, working capital mechanisms, and clear conditions to closing limits the buyer’s ability to introduce new terms during diligence. Vague LOI language creates room for retrading; precise language constrains it.
Typically four to eight weeks from the date the LOI is signed. The timeline depends on the complexity of the business, the preparedness of the seller’s documentation, and the buyer’s internal resources. Well-prepared sellers with organized data rooms and proactive financial documentation can compress the timeline significantly. Sellers who are disorganized or slow to respond can see diligence extend to three months or more, increasing deal risk.
A Quality of Earnings (QoE) report is an independent financial analysis prepared by an accounting firm that verifies the seller’s reported EBITDA. It identifies normalization adjustments, evaluates revenue quality, assesses working capital trends, and provides the buyer with a validated earnings figure. In most lower middle market transactions, the buyer commissions the QoE. Some sellers choose to prepare a sell-side QoE before going to market to identify and address issues proactively.
Yes. If due diligence reveals material issues not previously disclosed—such as EBITDA that is lower than represented, undisclosed liabilities, customer concentration risk, or legal exposures—the buyer may seek a price adjustment. This is called retrading. The best defense is thorough preparation: disclose all material issues before the LOI, ensure the financials are accurate and well-documented, and maintain competitive tension through the process.
At minimum: three to five years of financial statements and tax returns, monthly revenue detail, customer contracts, vendor agreements, employment agreements, organizational chart, insurance policies, intellectual property documentation, corporate records (articles, bylaws, shareholder agreements), and any pending or historical litigation. An experienced M&A advisor will provide a comprehensive diligence preparation checklist tailored to your business and industry.
For businesses with $2M+ EBITDA, a sell-side QoE is increasingly common and generally advisable. It allows the seller to identify and address financial issues before buyers discover them, establishes a credible, independently verified earnings figure that supports the asking price, and can accelerate the buyer’s diligence process. The cost—typically $30,000 to $75,000 depending on business complexity—is usually more than offset by the reduction in retrading risk.
It depends on the severity. Minor issues—a missing contract, an expired insurance policy—can typically be resolved without affecting the deal. Material issues—an undisclosed lawsuit, a major customer that is not under contract, or EBITDA that is significantly lower than represented—will prompt the buyer to request a price adjustment, additional indemnification, or changes to the deal structure. In the most severe cases, the buyer may walk away entirely. The best approach is to surface and address all known issues before diligence begins.
Findings during due diligence directly inform the representations and warranties in the definitive agreement, indemnification provisions, escrow amounts, and—in some cases—the inclusion of earnout provisions or holdbacks. For example, if diligence reveals customer concentration risk, the buyer may propose an earnout tied to retention of key accounts. If diligence identifies potential tax liabilities, the buyer may require a larger indemnification escrow. The non-compete agreement terms may also be influenced by what the buyer learns about the founder’s competitive significance during diligence.
Windsor Drake prepares founders for every dimension of due diligence—financial, legal, operational, and commercial—before the process begins. If you are considering a sale or preparing for a potential exit, a confidential conversation will help you understand what to expect and how to protect the value you have built.
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