No, flats are only part of it. Besides homes we clean offices, coworkings, salons and shops, do post-renovation cleaning in new buildings, dry-clean furniture and carpets, and clean up after events.
You choose the direction yourself. Some people prefer quiet regular flats with the same clients; others prefer offices early in the morning or late in the evening, when nobody is around. Post-renovation jobs are physically harder but pay more.
Dry cleaning is a separate speciality: it uses professional Kärcher extractors and requires additional training first. Cleaners who have mastered it earn more for the same hour.
You can change direction at any time — just tell your manager. Nobody will force you to travel only to offices if that does not suit you, and if you want to try different types of jobs, there is nothing stopping you. Different types can even be mixed within the same week.