Lead is a substance no one wants to find in his or her apartment, or the common area of building either. But it exists, and there are laws regulating who has to find it, who has to get rid of it, who's legally responsible, and who has to file lead notices with the city. The law specifically targets rental apartments, and this includes co-op or condo owners who sublet their apartments. Josh Koppel, President of H.S.C Management, shares the story of a client who had a lead problem in one of its apartments.