Hi Deviz,
Think how you would present the plans if you were drawing them by hand; which areas would you display on which floorplan?
Bearing this in mind, I would model the walls in single storey height segments, with their floorplan display set to 'Symbolic'. Set them to show on 'Home Storey Only' using the storey that they should display on as their 'Home Storey'.
Use 'Show on Home Storey Only' and 'Symbolic' for all other elements as well, and you should be able to adjust their heights and relative levels without them appearing on other storeys, and they will continue to look correct on the floorplan.
Hope that helps.