Every year, I watch business owners lose hundreds of thousands of dollars—sometimes millions—because they made avoidable mistakes in the months and years before listing their business for sale.
These aren't small errors. They're structural problems that erode value, scare off buyers, and turn what should be a profitable exit into a desperate fire sale. The worst part? Most sellers don't realize they've made these mistakes until it's too late to fix them.
Here are the seven most common—and most costly—mistakes I see in the Midwest market, along with what you need to do instead.
Most sellers call a broker when they're emotionally or financially ready to exit. The problem: by that point, your business value is what it is. If your books are messy, your customer base is concentrated, or you haven't hired a management team, you can't fix those issues in three months.
The right approach: Get a professional valuation 18-24 months before you plan to list. This gives you time to address value detractors—clean up your financials, diversify revenue, reduce owner dependency, and implement the systems buyers want to see. A restaurant owner I worked with increased his sale price by $400K simply by documenting his operations and training a manager to run the business without him. That took 18 months. He wouldn't have had time if he'd waited.
Action item: If you're within 5 years of a potential exit, get your valuation now. Not later. Now.
Yes, you can add back legitimate personal expenses to calculate SDE. But if you can't prove those expenses, buyers won't believe you. I've seen sellers claim $80K in addbacks with zero documentation—and buyers walked away or discounted the asking price by $250K.
Common undocumented expenses that kill deals: your spouse's "consulting fees" with no written agreement, personal travel disguised as business development, vehicle expenses with no mileage logs, home office deductions with no lease agreement.
The right approach: Document everything. If your spouse works for the business, they need a job description, regular paychecks, and W-2s. If you're expensing a vehicle, keep a mileage log. If you're running personal costs through the P&L, create a spreadsheet that categorizes every addback with supporting documentation.
What buyers will accept: Owner salary above market rate (with comp data), one-time legal or accounting fees (with invoices), owner health insurance (with policy docs), discretionary expenses like luxury travel (if clearly labeled and infrequent).
What buyers will reject: Vague "consulting" payments to family, unexplained credit card charges, round-number monthly expenses with no backup, anything that looks like you're hiding the real profitability.
Customer concentration is the #1 deal-killer in middle-market M&A. If one customer represents 30% of your revenue and they leave after the sale, the buyer just bought a business worth half of what they paid for it. That's an unacceptable risk, and buyers will either walk away or demand a massive discount.
I've seen businesses valued at $2M sell for $800K because 40% of revenue came from two customers. The buyers assumed (correctly) that those relationships wouldn't transfer.
The right approach: Start diversifying years before you sell. If you have a whale client, spend the next 2-3 years building out your customer base so no single client represents more than 10-15% of revenue. Yes, this is hard. Yes, it takes time. But it's the difference between a premium sale and a fire sale.
If you can't diversify in time: Get long-term contracts in place. A 3-5 year contract with your largest customer—with renewal terms and transferability clauses—can mitigate concentration risk. Buyers will still discount for it, but not as severely.
If the business can't operate without you, it's not a business—it's a job. And buyers don't pay premium multiples for jobs.
I see this constantly with professional services firms, construction companies, and specialized manufacturers. The owner is the only one who knows how to do the work, manage the clients, or run the operations. When the owner leaves, the business collapses. Buyers know this, and they price it accordingly.
The test: Can your business run for 30 days without you touching it? If the answer is no, you have a problem.
The right approach: Build a management team. Hire a GM or operations manager who can run day-to-day activities. Document your processes so anyone can follow them. Train your team to make decisions without you. This takes years, not months—which is why you need to start early.
Real example: A mechanical contractor I worked with was the only licensed master plumber in his company. He spent two years training and certifying two employees to take over technical work, then stepped back to focus on business development and strategic planning. His sale price increased by 40% because the business could operate without him.
Buyers pay for momentum. If your revenue is growing, they see opportunity. If it's declining, they see risk—and they either walk away or demand a steep discount.
This happens all the time. Owners mentally check out a year before they plan to sell. They stop pursuing new business, they let customer relationships slide, they defer maintenance and marketing. Revenue dips 10-15%, and suddenly their $3M business is worth $1.8M.
The right approach: Run your business like you're keeping it until the day you close. Don't take your foot off the gas. If anything, push harder in the 12-18 months before listing—launch a new service, expand into a new market, sign a big contract. Buyers will pay a premium for businesses with upward trajectories.
What if revenue IS declining? You have two options: wait until you stabilize and show 6-12 months of recovery, or accept that you'll need to discount your asking price to reflect the risk. There's no magic fix for this one.
I get it. You've built this business from the ground up. You've poured your life into it. It's worth more to you than any number a buyer will offer.
But the market doesn't care about your emotional attachment. It cares about cash flow, risk, and comparable transactions. If you list at 4.5x SDE when the market is paying 2.5-3x, you won't get any offers—or worse, you'll get lowball offers that insult you and poison the well with good buyers.
The right approach: Get an independent, third-party valuation from a credentialed professional. Not your accountant. Not an online calculator. A real business appraiser or M&A advisor who knows your industry and market.
Then, price your business at or slightly below the valuation. You're better off generating multiple competitive offers at a realistic price than sitting on the market for 18 months waiting for a unicorn buyer who will never show up.
Hard truth: In the Midwest, businesses typically sell for 10-20% below their listed price after negotiations. Factor that into your expectations from the start.
This one is self-serving, but it's true: the broker you choose will make or break your deal. I've cleaned up dozens of transactions that went sideways because the seller hired the cheapest broker, their cousin's friend who "does real estate," or tried to sell the business themselves to save the commission.
Here's what happens when you hire the wrong broker: your business sits on the market for 18 months with no traction, you field tire-kickers who waste your time, you leak confidential information to competitors, and you eventually sell for 20-30% less than you should have—if you sell at all.
What to look for in a broker: Industry expertise (they've sold businesses like yours), Midwest market knowledge (they understand local buyer expectations), a track record of closed deals (not just listings), and the capacity to manage the entire process from valuation to closing.
Red flags: Brokers who promise unrealistic valuations to win your listing, brokers who don't ask hard questions about your financials or operations, brokers who don't have a defined marketing process, and brokers who do this part-time or as a side hustle.
The DIY trap: Selling your own business to save a 10% commission sounds smart until you realize you left 30% of your value on the table because you didn't know how to negotiate, structure the deal, or navigate due diligence. Hire a professional. The good ones more than pay for themselves.
Avoid These Mistakes Before You List
Get a free, no-obligation valuation and find out what your business is really worth—and what you need to fix to maximize your exit.
Get Free AI Valuation → Talk to a BrokerThe Bottom Line
Selling a business is one of the most important financial decisions you'll ever make. The difference between doing it right and doing it wrong is often six or seven figures.
The sellers who get premium prices and smooth transactions aren't lucky—they're prepared. They start planning years in advance. They address the value detractors. They hire professionals who know what they're doing. And they run their businesses like they're keeping them right up until the day they close.
If you're reading this and thinking, "I've made some of these mistakes," don't panic. Most of them are fixable—if you have time. The key word is time. Start now, not later.
And if you're within 12-24 months of listing? Call a broker today. The clock is ticking.