The business case needed testing before the app.

Identify the critical assumption.

The critical assumption was that a provider could supply dependable data at a cost the subscription model could support. Building the interface would not resolve that uncertainty.

Examine the data and operating costs.

I recommended a focused paid discovery stage to assess data providers, model API costs and define a proportionate first scope. Those checks would give the client a basis for deciding whether to invest in the app and how the subscription tiers could work.

I set out what discovery should answer and defined the proposed scope. The resulting specification would belong to the client, so they could use it with me or take it to another developer.

Recommend a proportionate first investment.

The client received a written recommendation and a proposed discovery scope. It set out the questions to investigate before a build, leaving them free to decide whether to take that next step.