How many terminal models should an operator start with?

Few. An in-store MVP works with two or three certified Android terminals, one or two acquirers, and the sale, refund and end-of-day flows defined. A short catalog certified for every flow beats a long one that works only in some countries. Once the model reconciles in two markets, acquirers and devices can be added.

Few, fully certified

An in-store launch works with two or three Android terminal models, one or two acquirers, and the core flows defined and certified: sale, refund, cancellation and end-of-day. That is enough to onboard the first merchants in the first market and to see whether the transactions reconcile.

Why a short catalog wins

• Each model multiplies the certification work by the number of acquirers and countries.
• Support teams learn a few devices well rather than many devices badly.
• Spare stock and logistics stay manageable.
• Firmware and application updates are tested on a known set.

When to expand

When the model reconciles cleanly in two markets, meaning every terminal event lands in the transaction record and finance closes stores without manual work. Then add acquirers for new countries, devices for specific use cases such as unattended or mobile, and SoftPOS where it fits. Expansion driven by merchant demand and by proven reconciliation costs far less than a catalog built to impress at launch and certified only partially afterwards.