Due diligence is the stage where a buyer confirms the practice is genuinely what it appears to be. For a tidy firm it's straightforward and even reassuring; the friction and the surprises come from things that live only in the owner's head. This guide sets out exactly what a sensible buyer reviews, what each item tells them, the red flags that trigger a discount, and how to prepare a simple data room so the whole process is quick and calm.
The full document checklist
| What a buyer asks for | What it tells them |
|---|---|
| Fee analysis by client and service (3 years) | Recurring %, trends, service mix, hidden reliance |
| Top-10 clients as % of total fees | Client concentration risk |
| Client gains and losses (3 years) | Retention, momentum, any recent cluster of losses |
| WIP, debtors and lockup days | Billing discipline and cash health — and any hidden problems |
| Staff list: roles, contracts, salaries, tenure | Cost base, key-person risk, TUPE considerations |
| Engagement letters & AML records | Compliance hygiene and how up to date it is |
| PI insurance history & any claims/complaints | Risk profile and past disputes |
| Software & systems overview | How transferable and modern the operation is |
| Lease, premises & other commitments | Liabilities the buyer would inherit |
| Recent statutory accounts & management figures | Overall financial picture and profitability |
What each area really reveals
A good buyer isn't ticking boxes — they're reading the story behind the documents. The fee analysis shows how much income genuinely repeats and whether it's growing or drifting. Concentration and retention tell them how safe that income is. WIP and lockup are a proxy for how disciplined the firm is — high lockup can mean under-billing, scope creep, or work sitting unfinished. Staffing and engagement letters reveal key-person risk and compliance hygiene. None of these need to be perfect; they need to be visible and explained, not discovered late.
The red flags that trigger a discount
- Heavy concentration — one or two clients dominating fees.
- Everything through the owner — no documented processes, no second relationships, no delegated authority.
- Slipping retention or a recent run of client losses without explanation.
- Poor lockup — large WIP and aged debtors, suggesting billing or delivery problems.
- Gaps in AML or engagement letters — usually fixable, but they slow the deal and raise questions.
- Unresolved complaints or PI claims that surface late rather than being disclosed up front.
Few of these are deal-breakers on their own. What damages a deal is a buyer discovering them, rather than being told. Disclosure builds trust; surprises destroy it.
Build a simple data room
You don't need anything sophisticated — a single, well-organised cloud folder with the items above, kept current, is plenty. Structure it by section (fees, clients, staff, compliance, financials, premises). The payoff is threefold: it signals a well-run firm, it dramatically speeds the process, and it often supports a better valuation because it reduces the buyer's perceived risk. Preparing it also flushes out anything you'd want to tidy before a buyer sees it.
Prepare these first
- A clean fee analysis by client and service
- Up-to-date engagement letters and AML records
- A one-page staffing and systems summary
- WIP, debtors, lockup and retention figures
- A short, honest note on anything unusual — get ahead of it
Keeping it proportionate: light-touch vs heavy
Not all due diligence is equal. A large, multi-party, broker-led process can become a forensic audit of every file. A direct buyer who knows the sector can keep it proportionate — the essentials that actually affect value and risk, not a fishing expedition. That's one of the practical advantages of dealing directly: the person reviewing your firm is the person who'll run it, and they have every incentive to keep the process sensible and confidential.
What happens next
Once diligence confirms the picture, the deal moves to heads of terms — price, structure, timeline and your involvement — and then to completion and a protected handover.
Frequently asked questions
What documents do I need to sell my accountancy practice?
At minimum: a 3-year fee analysis by client and service, top-10 client concentration, client gains/losses, WIP and debtor/lockup figures, a staff list with contracts, engagement letters and AML records, PI history, a systems overview, and recent accounts. Keeping these in one organised folder speeds everything up.
What are buyers most worried about in due diligence?
Owner-dependency and client concentration, followed by retention trends and billing discipline (lockup). They're assessing how safe and transferable your income is once you're no longer running every relationship.
How long does due diligence take when selling a practice?
With a direct, sector-aware buyer and a prepared data room, it can be light-touch and quick — weeks rather than months. A multi-party broker process is usually longer and more intrusive.
Should I disclose problems before due diligence?
Yes. Disclosing issues up front — a lapsed engagement letter, a lost client, an old complaint — builds trust and keeps the deal on track. Problems discovered late do far more damage than problems disclosed early.
Thinking about your next chapter?
Whether you want to sell, step back gradually, or just take the back office off your plate — start with a confidential, no-obligation call with the buyer.
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