Due Diligence Red Flags Checklist

30 questions to ask before you sign the LOI

Every deal has risks. The difference between a good acquisition and an expensive mistake is knowing which risks matter — and which ones are dealbreakers. This checklist covers the 30 most common red flags we've identified across hundreds of lower-middle-market transactions. Use it as your first-pass screen before committing to full diligence.

Financial Red Flags

Revenue concentrated in 1–3 customers (>30% from any single customer)
EBITDA add-backs exceed 20% of reported EBITDA
Working capital has been systematically underinvested
Revenue growth is from price increases, not volume
Owner expenses run through the business (cars, travel, family payroll)

Customer & Revenue

No long-term contracts — all revenue is transactional
Customer churn is hidden by new customer acquisition
Top 3 customers represent >50% of revenue
Revenue quality is poor — one-time projects, not recurring
Customer satisfaction is untracked or declining

Operational

No documented processes — everything lives in the owner's head
Key equipment near end-of-life with no replacement plan
Single-source suppliers for critical inputs
IT systems are outdated, unsupported, or homegrown
Inventory is stale — >20% hasn't moved in 12 months

Management & People

Owner is the only person who can close sales
No second layer of management — flat org with owner as bottleneck
Key employees have no employment contracts or non-competes
Employee turnover is high or concentrated in key roles
Owner plans to leave immediately post-close with no transition

Market & Competitive

Market is shrinking or flat — no organic growth tailwind
New competitors entering with better technology or pricing
Business is vulnerable to disintermediation (platforms, direct-to-consumer)
No competitive moat — competes on price alone
Industry is consolidating and the target is sub-scale

Legal & Compliance

Pending or threatened litigation (even if "routine")
Environmental liabilities — especially in manufacturing/industrial
Regulatory exposure — industry facing new compliance requirements
IP is unpatented, unregistered, or poorly documented
Customer or vendor contracts are verbal/handshake only
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