Due Diligence Checklist
The complete data room for selling and buying a company — prepare, review, tick off.
Due Diligence Checklist
The complete data room for selling and buying a company — prepare, review, tick off.
- 80 review points across 11 areas, following the structure of a data room
- Both perspectives: seller preparation and buyer review in one list
- Fillable status fields — on screen or printed
- Quick check of the ten most common stumbling blocks
Who it is for.
The checklist is written for owners of small and mid-sized companies who want to prepare a sale, succession or investor entry in a structured way. It is equally suited to buyers — strategic acquirers, MBI candidates and financial investors — who want to assess a target company systematically.
Tax advisers, lawyers and management consultants who guide their clients through a transaction will find a concise working basis in the checklist to ensure completeness and clarity in the data room.
What you receive.
You receive a structured list of 80 review points, organised into eleven areas that follow the typical layout of a professional data room — from corporate and contract structure through finance, tax, employees and customers to IT, real estate and pending proceedings. Each point is phrased so that it works in both directions: for the seller to prepare and the buyer to review.
The PDF also contains fillable status fields that you can complete on screen or print out, plus a quick check of the ten most common stumbling blocks that regularly surface in due diligence and slow a transaction down.
How a Due Diligence actually runs
Due Diligence is the point at which an indicative offer turns into a binding price — or does not. Anyone who only starts preparing once the buyer sends the document request list loses time and negotiating position. The six phases below describe what happens in practice and what matters from the seller’s perspective.
Phase 1 · Vendor Due Diligence — the review before the review
Before a buyer sees the Data Room, the seller reviews himself. The aim is not window dressing but control: which contracts contain change-of-control clauses? Where are shareholder resolutions missing? Which licences run in the name of a private individual instead of the company? Every one of these points will be found in the buyer’s review anyway. The difference is whether you name it yourself and supply a solution — or whether the buyer discovers it and derives a price reduction from it. An honest Vendor Due Diligence six to twelve months before the process is the cheapest value lever there is.
Phase 2 · The Data Room — structure beats completeness
A Data Room with 800 unsorted documents is worse than one with 200 cleanly indexed ones. Buyers and their advisers work under time pressure and along checklists; what they cannot find counts as non-existent. What has proven itself is a structure organised by review areas — corporate law, finance, tax, contracts, employees, IT, real estate, compliance, insurance, litigation, environment — with a numbered index and one person responsible per area. Access rights are staged: first-round prospects see less than the bidder in the final round.
Phase 3 · Financial and Tax Due Diligence
This is where the purchase price is made. The buyer normalises your result: one-off effects, non-operating expenses, managing-director salaries above or below market level, private cost components, deferred investments. What remains is the adjusted EBITDA — the figure the multiple is applied to. On the tax side it is about open tax audits, hidden profit distributions, transfer pricing between affiliated companies and the question of whether loss carryforwards survive the change of ownership. Every unclear position costs either price or ends up in a warranty.
Phase 4 · Legal Due Diligence
What is reviewed is the chain: is the shareholder list complete? Are all capital measures cleanly documented? Are there pre-emption rights, options or side agreements from earlier investments? At contract level, notice periods, exclusivities, liability limitations and above all change-of-control clauses matter — a single one of them in a key customer contract can hold up a deal, because the buyer makes the customer’s consent a condition. In employment law, works agreements, pension commitments and the correct classification of freelancers count.
Phase 5 · Commercial and Tech Due Diligence
The commercial review asks whether your result is repeatable: customer concentration, contract terms, churn, pricing power, dependence on the owner. A company whose largest customer accounts for 40 per cent of revenue is valued differently from one with 200 customers. For technology-driven business models, Tech Due Diligence is added: code quality, technical debt, open-source licences and their copyleft effect, scalability of the architecture, bus factor in the development team and the state of the documentation.
Phase 6 · Findings, Disclosure and the purchase agreement
At the end there is a findings report. Every finding leads to one of four consequences: price reduction, a warranty in the purchase agreement, an indemnity for a specific risk, or a closing condition. What you set out in the Disclosure Letter can no longer be asserted later as a breach of warranty — full disclosure is therefore not a concession but your most effective liability protection. Parts of the purchase price frequently end up in an Escrow account or are tied to future results as an earn-out. The quality of your preparation determines how large those portions turn out to be.
You are still ahead of the review, not in the middle of it: Selling a company · Company valuation · M&A Data Room Manager
For a GmbH, buyers additionally review the shareholder list, the articles of association and shareholder resolutions — what this means for a GmbH sale is described separately.
Frequently asked questions.
In what format do I receive the checklist?
You receive the checklist as a digital PDF. The download begins immediately after payment; we also send the PDF and the invoice by email. You can fill in the status fields on screen or print the file.
Is the checklist suitable for sellers and for buyers?
Yes. The 80 review points are phrased so that they work in both directions: sellers use them to prepare the data room in a structured way, buyers use the same list to review systematically during due diligence.
Does the checklist replace a professional due diligence?
No. The checklist creates structure, completeness and transparency in the run-up to a transaction. It does not replace a guided commercial, financial, tax and legal review under mandate — but it makes that review noticeably more efficient.
Looking for concrete, individual support? An overview of our services can be found under Selling a company and Buying a company.