Customer interview questions
for commercial due diligence

Start from the claims, not from a script

Every information memorandum makes claims: net revenue retention is 115 percent, customers are sticky, the product is mission-critical, pricing has headroom, the competitive threat is weak. Customer interviews exist to test those claims. A generic satisfaction script produces a slide that says customers are happy and tests nothing. Write the claims down first, then write the questions that would confirm or contradict each one.

Who to interview

Ask the seller for the customer list, not the reference list. From it, and from public sources, select current customers across size and tenure, former customers who churned in the last two years, and prospects who evaluated the target and chose a competitor. Verify each participant's role and organisation before the call. A pre-LOI read needs six to eight; confirmatory diligence needs fifteen to thirty. A single interview with a churned customer is usually worth three with a reference.

Questions by claim

Retention and stickiness

How did you come to use the product, and who made the decision. What would have to happen for you to stop using it. When did you last seriously consider an alternative, and what stopped you. If the product disappeared tomorrow, what would you do on Monday. Which teams would notice.

Pricing power

What do you pay, roughly, and how has that changed. If the price rose 10 percent at renewal, what would you do. If it rose 25 percent. Who in your organisation would have to approve a price increase, and what would they ask. What else did you evaluate at the last renewal.

Competitive position

Who else do you know in this space, and what is your impression of each. Have you been approached by a competitor in the last year, and what happened. Where is the product weaker than alternatives. If a well-funded new entrant offered the same thing at 30 percent less, would you look.

Switching cost

What would switching involve in practice: data, integrations, training, contracts. How long would it take. Who would object. Have you switched a comparable tool before, and how did that go.

Service and product quality

Describe the last time something went wrong. How was it handled. What do you wish the product did. Has the pace of product improvement changed. How does the account team compare to others you deal with.

Ownership change

If the company were acquired by a financial investor, would that concern you. What would you watch for. Has a prior vendor of yours gone through a change of ownership, and what changed.

How to score what you hear

For each claim, mark each interview as supporting, contradicting or not addressing it, and note the verbatim that justifies the mark. Do not average sentiment. Three customers who would tolerate a 25 percent price rise and two who would leave at 10 percent is a finding about segments, not a 3.4 out of 5. Report the claim, the count, the strongest supporting and contradicting quotations, and your judgment. Sign it.

Record provenance

For each participant record role, organisation type, tenure as a customer, how they were reached, how their identity and role were verified, and what consent they gave. This appendix is what allows a lender, a co-investor or a vendor due diligence reviewer to trust the work without redoing it.

When to bring in Theory

When the deal team does not have the time or the off-list reach, Theory runs due diligence as a fixed-price Signal Brief or Decision Study. Every participant is verified and the researcher who runs the calls signs the recommendation.