Several sites recommend CHF 10 per team member per half day. One goes further, saying 20/person/day for 'easy' moves, where you have already packed up the boxes yourself, but for a full service move, CHF 30-50 per team member.
Interesting reading:
https://www.comparis.ch/immobilien/u...gsfirma-finden
https://www.guenstigerumzug.ch/zuric...und%20CHF%2010 .
https://www.kleiner-bastler.ch/sollt...inkgeld-geben/
Whatever you do, make sure to offer cold drinks or coffee throughout the day.
Hope the move goes well.
ETA:
Well, it would help if I could actually see to read. Just realized you are asking about move out cleaners, not movers. In that case, from Comparis:
https://www.comparis.ch/immobilien/u...inigungsfirma#
No requirement to tip, but if you are happy CHF 10 per cleaner.
< Trotting off to find that application for a guide dog...>