But what do you mean by "tap water card for the sixth and seventh floors"? Do you mean to use the water meter of the water company on the sixth and seventh floors?
I guess you are on the seventh floor. When buying a house, are the sixth and seventh floors separate real estate licenses, and are they two unrelated suites? If that's the case, I suggest you go to a real estate company, because there are relevant regulations in the State Council, which clearly require that each household's water, electricity and gas should be measured separately. If the real estate company sells the houses on the sixth and seventh floors as suites, it has nothing to do with the real estate company.