If i may ask : If i have a 2nd living hall which has 16-18 ft height and i wish to built 1 floor on top of the living hall like what u see in SUbang SOHO unit ,just to built the platform and the staircase would cost how much ? size may be... 15x10ft =150sf.

no high5 material, just use timber flooring and wish to put a king size bed and TV set there so need to be sure it holds the weight too. thanks for sharing.