As a business broker, I see the same preventable issues scupper deals time and again. The good news? Most of these problems are fixable if you address them before going to market. Here are the five common deal-killers and what you can do about each one.
1. Customer Concentration
The problem: When one or two customers account for more than 25% of your revenue, buyers get nervous. They’re not just buying your business; they’re betting that those key accounts will stick around after you leave. If your biggest customer represents 40% of turnover, a buyer sees a business that’s one phone call away from disaster.
How to fix it: Ideally, start diversifying your customer base 18–24 months before selling. Actively pursue new accounts, even if growth feels slower than doubling down on your biggest clients. If diversification isn’t realistic in your timeframe, focus on strengthening those key relationships in ways that survive your exit: long-term contracts, relationships with multiple contacts at the customer (not just one decision-maker), and documented service level agreements.
Be prepared to offer an earnout structure or extended handover period that gives buyers confidence those accounts will transition smoothly if you rely on just a few key customers.
2. Owner Dependency
The problem: If the business can’t function without you, buyers aren’t purchasing a company they’re purchasing a job. This is especially common in professional services, trades, and founder-led businesses were client relationships, technical expertise, or day-to-day decision-making all flow through one person. This is probably the most frequent deal destroyer I come across.
How to fix it: Start extracting yourself from operations well before you list. Document your processes, not in a dusty manual nobody reads, but in practical, accessible systems your team actually uses. Delegate client relationships to senior staff. Promote or hire a second-in-command who can run things during your two-week holiday without the wheels falling off.
The litmus test: could you take a month off and return to a business that’s still ticking over? If not, that’s the gap you need to close. Buyers will pay a premium for a business with a strong management team in place. They’ll discount heavily, or walk away from one that’s entirely dependent on the departing owner.
3. Messy Financials
The problem: Incomplete records, aggressive personal expenses run through the company, inconsistent reporting, or management accounts that don’t reconcile with filed accounts. These issues don’t just make due diligence painful; they erode buyer confidence. If they can’t trust the numbers, they can’t trust the business.
How to fix it: Get your financial house in order at least two years before a planned sale. Work with your accountant to ensure your management accounts, VAT returns, and Companies House filings all tell a consistent story. Strip out personal expenses or discretionary costs that won’t transfer to a new owner and document these as “addbacks” clearly so buyers can see the true earnings potential.
Consider having a reporting accountant review your figures before going to market. It’s an upfront cost, but it dramatically speeds up due diligence and signals to buyers that you’ve nothing to hide.
4. Undisclosed Liabilities and Legal Issues
The problem: Outstanding HMRC disputes, pending employment tribunal claims, unresolved debts/ loans that should have been written off, unresolved customer complaints, environmental issues, or intellectual property that isn’t properly protected. Buyers will find these during due diligence and discovering them late in the process destroys trust. Even if the issue is manageable, the surprise factor can kill a deal.
How to fix it: Conduct your own due diligence before buyers do. Audit your legal position: are your employee contracts up to date? Do you own your trademarks and domain names outright? Any outstanding disputes with HMRC, creditors, or former staff. Leasehold issues with your premises? Also write off debts (legitimately) well in advance of going to market?
Disclose known issues early, with a clear explanation of how they’ve been managed or resolved. Buyers can often accept imperfections, what they can’t accept is feeling blindsided. If there’s something material lurking, it’s far better to address it proactively than have it blow up the deal at the eleventh hour.
5. Unrealistic Valuation Expectations
The problem: You’ve heard that businesses in your sector sell for “five times profit” or you’ve seen a competitor’s rumoured sale price. You arrive at a number that reflects what you need for retirement rather than what the market will actually pay. Overpriced businesses sit on the market, attract tyre-kickers, and ultimately sell for less than they would have with realistic pricing from the start.
How to fix it: Get a proper, independent valuation—ideally from a broker or corporate finance adviser who specialises in your sector and transaction size. Understand that valuation multiples vary enormously based on size, growth trajectory, recurring revenue, margin quality, and dozens of other factors. A £500k profit business does not command the same multiple as a £5m profit business.
Be honest with yourself about what’s driving your number. If there’s a gap between what you need and what the market will pay, you may need to delay your exit, improve the business, or adjust your post-sale plans.
The Bottom Line
The best time to prepare for a sale is long before you’re ready to sell. Ideally, you’re running your business as if it could be sold at any moment—clean financials, diversified customers, systems that don’t depend on you, and no skeletons in the cupboard.
If you’re thinking about an exit in the next couple of years, start addressing these issues now. A business broker can help you identify gaps and create a realistic timeline for getting sale-ready.
The owners who achieve the best outcomes aren’t necessarily running the biggest or most profitable businesses. They’re the ones who prepare properly—and leave nothing for due diligence to uncover that they haven’t already addressed.
If you want to talk about selling your business contact Rupert Trevelyan of Weybrook Business Brokers at rupert@weybrookbusinessbrokers.com