Check FB for "Clean it yuhself".
You can rent a commercial floor cleaner for a day. They supply everything you need including the cleaning products.
If you like, have this left over from when I used their equipment two years ago. You are welcome to have it.
I used this on porcelain tiles and it worked great. There is more than half bottle. Or you can try to source it yourself.
If you in Central, I can meet you somewhere. PM me if interested.