Due Diligence Checklist Before Selling a Digital Business | Astora Group

Complete due diligence checklist for digital business sellers: financial documents, buyer verification requirements, and preparation steps to maximize valuation.

Diligence is the process of verifying the information you've provided about your business—revenue, traffic, contracts, customer retention, technical infrastructure—so the buyer can confirm that claims are true, accurate, and current. Most sellers encounter the diligence checklist for the first time after signing a letter of intent, when the buyer's advisor sends a request list and a deadline. That timing is a problem. The sellers who get the best outcomes treat document preparation as something that happens before they go to market, not in response to buyer pressure after a deal is already in motion. related guide related guide related guide related guide related guide

This guide walks through the key workstreams buyers assess, what moves the multiple during diligence, and the practical steps you should take months before you list your business for sale.

How diligence connects to valuation

Valuation multiples for digital businesses vary sharply by asset type, maturity, and earnings predictability. SaaS businesses commonly range from 3× to 10× annual recurring revenue (ARR) depending on growth and churn, with top performers earning premiums. For smaller SaaS under $5M ARR, seller's discretionary earnings (SDE)-based valuation is often more suitable than market approaches.

E-commerce revenue multiples normalised to 2.83× by late 2024, according to Windsor Drake's e-commerce valuation report. Current SDE multiples for e-commerce businesses range from 2.0× to 4.0×, with well-established brands commanding 4.0× to 5.0×+. For subscription e-commerce, models with strong retention can command 4.0× to 10.0× ARR depending on growth rate and churn.

Digital agencies with an average adjusted EBITDA of $2.4 million achieved an average multiple of 6.46× in recent transactions, with some reaching as high as 12× for strategic buyers, according to Breakwater M&A.

The choice between SDE and EBITDA is critical. If you are selling to an individual buyer who will operate the business themselves, SDE is appropriate. If you are selling to a private equity firm or strategic acquirer who will install professional management, EBITDA is the relevant metric. Using the wrong earnings basis misframes the entire valuation conversation and can cost you 1–2× in multiple.

Owner-operated digital businesses are commonly priced off profit or EBITDA and then adjusted up or down for quality signals during diligence. The baseline multiple is your floor; diligence determines if you move up or down from there.

What compresses versus expands a multiple

Buyers adjust multiples during diligence based on concrete, verifiable factors. Here's what actually moves the needle.

Factors that expand multiples (earn premium)

Recurring, contracted revenue: Annual contracts with auto-renewal, standardised pricing, and clear expansion mechanics produce higher-quality revenue than month-to-month arrangements. Transitioning from monthly to annual contracts, and custom to standardised tiers, before a process measurably improves buyer appetite and multiple.

Ownership independence: Agencies where revenue is tied heavily to the founder face substantial valuation discounts, according to Breakwater M&A. Conversely, businesses that generate revenue independently gain premiums.

Customer diversification: Having no single client represent more than 15–20% of revenue reduces risk.

Margin strength: Above-industry-average margins indicate operational moat and pricing power. Margins 200–300 basis points above industry average typically add 0.25× to 0.75× to the multiple.

Proven unit economics: Buyers care intensely about customer acquisition cost (CAC), lifetime value (LTV), payback period, repeat purchase rate, and how these have trended. The 2020–2022 era of paying for high-growth-low-margin direct-to-consumer brands is over; buyers in 2026 want unit economics that already work.

Factors that compress multiples (red flags in diligence)

Technical debt and outdated infrastructure: Legacy systems, inefficient coding practices, or architectural weaknesses could impact the maintainability and future development of the software. Excessive technical debt may require significant post-acquisition investment to modernise the technology stack, according to Meridian Trust.

Cybersecurity and data governance gaps: Cybersecurity due diligence assesses the security of digital assets, data protection practices, history of breaches, and vulnerability management. This is critical for identifying potential cyber risks that could lead to financial loss or reputational damage, according to Cisive.

Undocumented or platform-dependent revenue: QuickBooks exports and spreadsheet metrics invite scepticism that manifests as lower bids and retrade risk.

Revenue spikes tied to one-off events: Normalisation must address pandemic-era revenue spikes (2020–2022 should be treated as anomalies, not baselines), one-time marketing spend versus recurring CAC, owner personal expenses run through the business, inventory write-offs and obsolescence, shipping cost fluctuations, and Amazon or marketplace fee changes.

What buyers actually check: key diligence workstreams

Financial diligence

Buyers typically begin by asking for financial records from the past three to five years, including tax filings, bank statements, and detailed financial reports, according to Windes. Ensure you have at least three years of audited financial statements, including income statements, balance sheets, and cash flow statements.

A Quality of Earnings (QoE) report is an independent financial analysis, typically prepared by a third-party accounting firm, that documents add-backs, normalises owner compensation, and assesses the reliability of reported earnings. Sellers in the lower middle market increasingly commission their own QoE before going to market, because it shifts the burden of proof: rather than defending your numbers under buyer pressure, you present a documented third-party analysis.

Legal and intellectual property

Intellectual property due diligence includes all copyrights, trademarks, patents, formulas, digital information, and other exclusive intellectual property owned by the business, according to The Hartford. Strategic buyers will often run an independent software scan to understand that the business has the proper licences for open source software they're using.

Customer and revenue diligence

Buyers and investors like to get an understanding of opportunities within your customer base. Specifically, they might look for potential cross-selling opportunities or product gaps to reduce future churn, according to Vistapoint Advisors. For audience-led businesses like those Astora targets, this means clarity on organic traffic sources, email list health, subscriber retention, and channel independence.

Technology and infrastructure

Technology and IT infrastructure assessment evaluates the target company's technology assets, IT infrastructure, digital capabilities, cybersecurity posture, software licences, and any technology-related risks or opportunities that could significantly impact operations and valuation, according to Diligent.

Analyse the company's API structure and integration potential with third-party services. Strong API capabilities are essential for business expansion, seamless product integration, and adaptability to customer needs, according to Meridian Trust.

Ownership and governance

Corporate governance documents help buyers and investors structure the deal for tax purposes. A capitalisation table will help them understand how to structure the deal, including equity rolls and liquidity considerations, according to Vistapoint Advisors.

Preparing for diligence: practical steps

Start before you go to market

More than 90% of sell-side due diligence involves anticipating what information buyers will be asking for, and assembling it in a way that makes the case for your business as powerfully and accurately as possible. The other 10% focuses on researching your potential acquirer, according to Website Closers.

Build a data room early

A data room is a secure, organised repository of the documents a buyer will review during due diligence. It can be a virtual platform or, for smaller transactions, a structured shared folder. The key is organisation: documents should be clearly labelled, logically grouped by category, and current.

Normalise your financials before diligence begins

When using EBITDA multiples, what buyers really evaluate is adjusted EBITDA. This means financials should reflect the company's true operating profitability by adding back owner's personal expenses that will not continue after a sale, normalising for a market-based salary and benefits package for the leadership team, and removing any one-time, non-recurring expenses or unusual income, according to GSquared CFO.

Consider commissioning a sell-side QoE

Once a buyer issues an LOI based on your stated SDE, they will run a formal add-back challenge during due diligence, either internally or via a Quality of Earnings (QoE) provider. Both scenarios pay for the £20,000–£40,000 QoE multiple times over. The QoE also accelerates the buyer's due-diligence timeline by two to four weeks, which reduces deal-fatigue risk.

Audit technical infrastructure and security posture

Run an independent audit of your technology stack, API integrations, open source licences, and cybersecurity protocols. Identify technical debt, document architectural decisions, and map dependencies on third-party services. Cyber Husky's IT due diligence checklist notes that buyers will assess your security practices, vulnerability management, and data protection measures closely.

Document customer and revenue quality

Prepare cohort-level retention data, customer acquisition cost (CAC) by channel, lifetime value (LTV) by segment, and concentration metrics. For e-commerce businesses, include repeat purchase rates, average order value trends, and margin by SKU. For newsletters, document open rates, click-through rates, unsubscribe rates, and revenue per subscriber over time.

Frequently asked questions

When should I start preparing for diligence?

Ideally 12–24 months before you plan to go to market. That gives you time to clean up financials, reduce owner dependency, diversify your client base, and strengthen contracts before buyers start diligence. Most sellers encounter the diligence list for the first time after signing a letter of intent, when the buyer's advisor sends a request list and a deadline. That timing is a problem. The sellers who get the best outcomes treat document preparation as something that happens before they go to market, not in response to buyer pressure after a deal is already in motion.

What if I have messy or incomplete financial records?

The answer depends less on what is in your business than on how well you understand it, how clearly you can explain it, and how organised you are when the scrutiny arrives, according to Viking Mergers. Start organising now. Even if records are incomplete, systematic assembly signals professionalism and reduces buyer scepticism.

Should I fix problems proactively before the sale?

Yes. There are proactive steps you can take to show your business in the best light possible. If there are problems, you can choose to fix them proactively. For example, maybe your computer network is outdated and can't handle your current inventory needs. If you go ahead with the upgrade, then there's nothing to disclose, according to The Hartford.

What's the difference between SDE and EBITDA for my valuation?

SDE adds back the owner's salary; EBITDA leaves a market-rate manager salary in place. SDE assumes the buyer will run the business themselves and replace the seller's compensation with their own. For the same business, SDE will be higher than EBITDA by the difference between owner compensation and market-rate manager compensation, according to CT Acquisitions.

How much time do I need to prepare before going to market?

Ideally 12–24 months. That gives you time to clean up financials, reduce owner dependency, diversify your client base, and strengthen contracts before buyers start diligence.

What happens if the buyer discovers something unexpected during diligence?

Due diligence is usually an important condition in the buyer's offer in almost all sales. If any problems are discovered during the process, they may be addressed before finalising the deal, according to The Hartford. Transparency and early disclosure typically yield better outcomes than surprises.

If you're preparing to sell a digital business—whether SaaS, e-commerce, newsletter, or content site—start building your diligence materials today. You can explore how buyers assess different asset types in our valuation guide, or use our business valuation tool to estimate where your business might sit. When you're ready, learn more about what we buy and how we work with founders who've already earned their audience.

Last verified: January 2025

Diligence Checklist Before Selling a Digital Business