Founders who've been through VC due diligence once never describe it as a pleasant experience. It's thorough, it's pressure-tested, and it exposes every assumption you've made about your business. For vertical SaaS companies, due diligence has a specific shape that's different from what most horizontal SaaS playbooks describe.
The questions investors ask when evaluating a CRM for any company are different from the questions they ask when evaluating dispatch software for independent plumbers. The market concentration, the customer profile, the switching costs, the competitive dynamics — all of it is specific to the vertical. Investors who know the space will know it. Prepare accordingly.
Why Vertical SaaS Diligence Is Different
The standard SaaS diligence checklist covers metrics (ARR, MRR, churn, expansion), technical architecture, customer interviews, and team assessment. All of that applies to vertical SaaS too.
What's different is what those metrics mean in context. A 15% annual churn rate is a red flag in horizontal SaaS. In a market where the underlying businesses themselves churn at 10% per year — think independent restaurants, small trades contractors — 15% churn might mean you're losing zero customers to competitors. Investors who understand vertical markets know to contextualize their metrics. Investors who don't will penalize you for something that isn't a problem.
The implication: prepare the context, don't wait to be asked. Walk investors through how to read your metrics correctly before they walk themselves to the wrong conclusion.
Market Size and Addressability
Vertical SaaS due diligence always starts with TAM — and it's more contentious than founders expect.
The question isn't "how big is the market." It's "how big is the market you can actually capture, at what ACV, with what payback period." Investors will build the model themselves. If your numbers don't survive their model, you'll hear about it in the term sheet conversation, not before.
Use your operator knowledge to be specific: how many businesses fit your target profile, how you've segmented by size, what the realistic ACV range is, where the expansion revenue comes from. If your market has 8,000 potential customers and you can defend a $12,000 ACV with 95% GRR, an investor will build a credible path to $96M ARR. That's a fundable ceiling. If you walk in without that math prepared, you're leaving the TAM argument in their hands.
Customer Concentration and Cohort Health
In vertical SaaS, customer concentration is common and not automatically a red flag — but investors will probe it.
If your top 5 customers represent 60% of ARR, diligence will focus on what happens if one churns. Be ready to explain the relationship, the contract terms, and why that customer is sticky. If you can't explain it clearly, the concentration becomes the problem.
Cohort health is where the real story lives. Show monthly cohort data going back to your first customer. Investors want to see flat or growing cohorts 12-18 months after initial contract. If a cohort is declining, they'll want to understand why and whether it's structural or a one-time event.
For operator-founders, cohort data often tells a compelling story: your direct-network customers (the first cohort) are the stickiest. Newer customers acquired through less personal channels are performing similarly. That tells investors the retention isn't about founder relationships — it's about product stickiness.
Competitive Moat Assessment
Every vertical SaaS diligence includes a competitive landscape review. Investors check whether you have a real moat or just a temporary lead.
In vertical markets, legitimate moats come from a few specific sources:
- Data moat. If your customers have 24 months of operational history in your system, migration means starting over. What data are you accumulating, and how does it make the product harder to leave?
- Workflow integration depth. Software that runs a company's payroll processing and scheduling is harder to rip out than software that handles one-off reporting.
- Industry-specific compliance. In regulated verticals — healthcare, legal, financial services — compliance requirements create switching costs unrelated to product quality.
- Network effects. If your product creates value between customers in the same market — shared vendor networks, benchmark data — that's a network moat.
Be ready to explain your moat in specific terms. "Our customers love us" is not a moat. "Our customers have 3 years of equipment service history in our system and their technicians use our mobile app 40 times per day" is a moat.
Team and Domain Expertise
For operator-founders, team diligence usually goes well. Investors are checking whether you actually understand the market as deeply as your pitch claims — and if you've spent 10 years running a business in the vertical, that question answers itself.
What investors probe more carefully:
- Whether you have or can hire the technical depth to build what you're promising
- Whether the management team can execute at the scale a Series A investment requires
- Whether your domain expertise covers the buying center, not just the end user
That last point matters. The decision-maker for a $15,000 ACV software purchase isn't always the person who uses the product every day. If you've spent your career on the operations side, you may know the workflow cold but have limited relationship with the CFO or the ownership group who writes the check. Investors will ask about it.
Preparing well for vertical SaaS due diligence is mostly about knowing your numbers, knowing your customers, and being honest about what you've proven versus what you're projecting. Pitch us the business — we'll look at it from both sides of the table.