What this is: one ordinary business, three steps — the routine it runs today, the build that replaces it, the month the build pays for itself. A pattern, not a case study about one lucky client. If your business looks like this one, the shape transfers.
01 · The routine today
Orders come in → someone copies the address into a shipping label site, types the invoice, updates the sheet, emails the tracking number. 45 minutes per order batch, ~120 orders/mo ≈ €900/mo (the shop owner's own evenings, which is why it never shows up in any budget).
02 · The build
Order → invoice → label → tracking-email glue: a small app that watches the shop's orders and does the assembly, with one human pass for anything weird. The €690 tier if the shop platform has no API to lean on, €390 if it does. Delivered as your code, in your repo — when your shipping provider changes, you edit one file instead of waiting for a vendor's roadmap.
03 · The crossover month
Month 3 on the pessimistic €690 version. On the €390 version, month 2. Either way, the evenings come back first.