Coffee Appreciation

Nope, you have to have a toilet for the staff, which must also have a handwash basin that is not used for any other purpose than handwashing.

No requirement to provide evacuation facilities for the punters.

I think you only need access to a toilet, rather than your own toilet for staff.

Is there a map of london and with all the good coffee shops marked on it?
I'm walking from Euston to Mayfair tomorrow and might need some pointers.