Language pair multiplied by document type gives you the actual map of the market. "Spanish to English certified" and "German to English technical" are two different businesses, and every crossing that gets its own page picks up enquiries that would otherwise never arrive at all.
The purpose sits inside almost every query — for a visa application, for a university, for a tender. Picking up that purpose and explaining exactly what the receiving body requires builds trust long before price is discussed, and it's the part almost no competitor bothers to write.
Certified work comes from nearby, because people still want to hand over or collect originals; specialist translation comes from anywhere. So one half needs a well-kept Google Business Profile and the other needs pages that stand up with no town name in them at all.
Turnaround is a ranking asset as well as a selling point. "Same day certified translation" is a real search with very little competition, and an honest page about what can and cannot be done in a day answers it better than a promise nobody keeps.