Every buyer has a moment in diligence when something doesn’t match. A customer is smaller than described. A contract has a change-of-control clause. A key employee is planning to leave. The question isn’t whether surprises show up. It’s whether you find them before closing or after.
I buy businesses for my own account, so this isn’t theory for me. Here’s how I think about diligence — and what sellers should expect from serious buyers.
What due diligence is for
Diligence has three jobs:
- Verify. Confirm what the seller has represented: revenue, earnings, customers, assets, people.
- Discover. Find what hasn’t been said: risks, liabilities, dependencies, problems.
- Plan. Learn enough to run the business well from day one. See post-acquisition integration.
What you learn can change price, structure, terms — or whether you buy at all.
When diligence happens
Light diligence starts the moment you see the confidential information package. Deep diligence usually begins after a letter of intent is signed and the seller grants exclusivity. See letter of intent. The LOI typically sets a diligence period and what access you’ll get.
The four big areas
1. Financial
Are the earnings real, repeatable and transferable? Tax returns tied to financial statements, bank deposits tied to revenue, add-backs supported, working capital understood, customer concentration measured. See financial due diligence.
2. Legal
What does the buyer inherit? Entity records, contracts and assignability, leases, litigation, permits and licenses, intellectual property, employment matters, tax liens and compliance. See legal due diligence.
3. Operational
How does the business actually work? People, processes, systems, equipment, suppliers, customers and the owner’s real role. See operational due diligence.
4. Commercial and market
Why do customers buy, and will they keep buying? Competition, pricing power, market trends, reputation and growth opportunities.
Who does what
| Area | Typical lead |
|---|---|
| Financial | Buyer plus CPA or quality-of-earnings provider |
| Tax | CPA |
| Legal and contracts | Buyer’s attorney |
| Lender requirements | Lender, including any required valuation |
| Insurance | Insurance broker |
| Environmental, real estate | Specialists as needed |
| Operations, people, customers | Buyer |
A practical diligence process
- Start with a request list organized by area, prioritized by what could kill the deal.
- Use a data room so documents are organized and access is tracked.
- Go deal-breakers first. Test the biggest risks — earnings quality, customer concentration, key contracts — before spending heavily on the rest.
- Meet the business. Site visits, observing operations, talking with the seller at length.
- Talk to people, carefully. Key employees, customers and suppliers — only when the seller agrees and timing protects confidentiality.
- Track issues in a single list with severity and a proposed resolution: price, structure, a closing condition or walk away.
- Negotiate findings into the purchase agreement. See purchase agreement.
How findings change a deal
- Price adjustments when earnings are lower than presented.
- Structure changes — more seller financing, an earnout or holdback where results are uncertain. See earnouts.
- Specific protections — indemnities, escrows, representations and warranties.
- Closing conditions — a key contract assigned, a lease extended, a lien released.
- Walking away when a risk can’t be priced or fixed. See red flags when buying a business.
South Carolina-specific diligence
In South Carolina, one item every buyer of business assets should know: under SC Code §12-54-124, a seller’s unpaid state taxes can become a lien on the transferred business assets unless the buyer obtains a certificate of compliance from the SC Department of Revenue dated within thirty days before the transfer. Build that into your closing checklist with your attorney. Also check county business licenses, SC Secretary of State entity records, and any state professional licenses the business depends on. See South Carolina acquisition checklist.
For sellers: how to make diligence painless
- Prepare before you list. Clean books, organized contracts, documented add-backs. See prepare a business for sale.
- Disclose problems early. Buyers forgive problems you disclose. They don’t forgive problems they discover.
- Respond quickly. Slow responses make buyers nervous and deals tired.
- Keep running the business. A performance dip during diligence is one of the most common reasons deals get repriced.
What it costs to skip diligence
Buyers who rush diligence find out later — when a customer leaves, a tax notice arrives or a key employee walks out. Sellers who resist diligence lose serious buyers and keep the tire-kickers. Diligence done well protects both sides and gets more deals to the closing table.
Diligence fatigue is real
Long diligence wears everyone down. Sellers get tired of requests; buyers get tired of waiting; momentum fades and small issues start to feel like big ones. The cure is a clear timeline, a weekly check-in with both sides, and the discipline to resolve issues as they surface rather than letting them pile up for the end. When I buy, I try to tell sellers upfront what I’ll ask for, in what order, and why — so nothing feels like a surprise or a fishing expedition.
How I approach diligence as a buyer
I focus first on what would stop me from buying, so a seller doesn’t waste weeks on a deal that won’t close. I explain why I’m asking for something. I’m careful about when and how I talk to employees and customers. And I treat what I learn as confidential, because the business has to keep running whether or not we close. See how selling to Ben works.
Next steps
Dig into financial due diligence, legal due diligence and operational due diligence. If you’re buying or selling in South Carolina and want to compare notes, talk to Ben about acquisitions.
A starter diligence request list
Every deal is different, but most serious buyers ask for some version of this list early on:
- Financial: several years of tax returns and financial statements, monthly statements for the recent period, the general ledger, bank statements, receivable and payable agings, a schedule of add-backs with support, and a debt schedule.
- Customers: revenue by customer over time, contracts, pricing history, and any customers lost recently and why.
- People: an organization chart, roles, tenure, pay structure, key-person dependencies and any employment agreements.
- Operations: a description of how work is sold, scheduled, delivered and billed, with the software used at each step.
- Assets: equipment and vehicle lists with condition and age, leases, and any real estate.
- Legal: entity documents, material contracts, licenses and permits, insurance policies, and any claims or disputes.
Sellers who have this ready before an LOI shorten diligence dramatically. Buyers who send it in priority order — deal-breakers first — make the process feel respectful rather than endless.
What diligence can’t do
Diligence lowers risk. It doesn’t remove it. No amount of document review predicts every customer decision, employee reaction or market shift after closing. That’s why good deals combine diligence with structure — seller transition support, sensible financing and protections in the purchase agreement — and with a real plan for the first months of ownership.
Questions people ask
What is due diligence when buying a business?
Due diligence is the buyer’s investigation of a business before closing — verifying financials, reviewing contracts and legal matters, understanding operations, people and customers, and identifying risks that affect price, structure or whether to proceed.
How long does business due diligence take?
It depends on the size and complexity of the business, how organized the seller’s records are, and lender requirements. Smaller, well-prepared businesses move faster; complex or disorganized ones take longer. The letter of intent usually sets a diligence period.
Who performs due diligence?
The buyer leads it, typically with a CPA or quality-of-earnings provider for financials, an attorney for legal matters, the lender for its own requirements, and specialists such as environmental, insurance or IT reviewers when needed.