Satin brass and matte black are living finishes: they survive years of daily use and die in one afternoon of the wrong cleaner. The rule is simple. Warm water, a drop of dish soap, a soft cloth. Nothing else.
Ammonia glass cleaners, vinegar, and anything labeled lime or scale remover will strip the finish at the edges first, which is exactly where the customer looks. Tell the homeowner at handoff; it saves the warranty conversation later.