We just redid two bathrooms with porcelain tile instead of marble. I was told to only use non- bleach cleaners and no vinegar. Installer said as an extra precaution to seal grout and use scrubbing bubbles on shower area (polished porcelain) and wet mop floor which is honed.

I replied to your other post.

Any good cleaner that is "Neutral PH."

You would have good luck steaming. The Dupray Neat is on amazon and works great. Excellent results for not a ton of money.