I just had a great experience with Total-Reinigung in Zurich, I was recommended to use them based on this site. They cleaned my ~35 sq. m. flat for less than 500 CHF and I passed the inspection with ease. The fellow who came by, I think Artur, was really warm and kind. He did a pre-inspection, cleaned, and then showed up for the inspection with the landlord. He made quick work of anything she asked to be polished up.
This made leaving Switzerland a whole lot less stressful! I highly recommend it.
By the way, these guys like to be paid in cash. He trusted me to send a transfer, but it's not normally the case given the fact of many people leaving the country, etc.