Choosing between a SaaS platform and custom software: a founder's checklist

The honest first question

Before any build-vs-buy analysis: is the workflow you need actually differentiating? If your invoicing works like everyone else's, subscribe to invoicing software. Custom software earns its cost only where your process is the product.

The checklist

1. Differentiation. Does this system encode something competitors cannot copy by buying the same tool?

2. Volume economics. SaaS pricing scales per seat or per transaction. Past a threshold, owning the software is cheaper — find that line before signing either contract.

3. Integration depth. If the tool must talk to three internal systems and a government portal, integration cost can exceed build cost.

4. Data gravity. Whose database does your business live in after three years? Export clauses matter more than feature lists.

5. Change velocity. If your process changes monthly, a vendor roadmap will always lag. If it changes yearly, do not pay for custom flexibility you will not use.

When we say no

We regularly advise prospects to use off-the-shelf tools — a CRM, a help desk, an accounting package — because a custom build would be a worse outcome. That honesty costs us small projects and wins us the right ones.