[mike roberts]

So Mike what does the client want, just a clean-up to sell or a full blown clean?

He is after the moss / lichen being removed - without harming the tiles -- instant results - but doesnt want them to stand out -----
so not much really     seems like one of my normal customers 

to be honest mate, I view it in a similar way to chewing gum removal - if you are doing the job - do it properly dont just remove the gum (spot clean) clean all the paving back to new. Same as roof cleans - clean the whole roof then no one has any comebacks we all know where we stand - thanks for your inputs appreciate it.

[Roger Oakley]

OK so if you  can forget the recycling route then I would use hypo 2:1, pre-wet first then apply the hypo, dwell for 20-30 mins, then low pressure off, you would have to make the call re wind drift, run-off etc, if you have any stubborn lichen, then spot clean with the hypo after the first clean. Anything else sounds like it is not what your client wants.