Does new landed property have comon water tank for the whole taman? Or water coming direct from air Selangor?

Usually it depends on the size of the overall development. Hence the answer can be yes / no. For big size development, usually the water utility company will required the developer to build the elevated water tank to cater for the overall development. If the land size of the housing is small / not sizeable, usually it will share with other neighboring housing estate.

The water infrastructure before the water meter belongs to AIR Selangor property. The elevated water tank external also belong to Air Selangor. Hence, water from external elevated water = water source from Air Selangor.