Think about how you would build it in the real-world. Model it the same way.
...you have already used three of tools that you need to use to model it. Roof, Walls and Floors. All those, plus Columns, will be all you need to model it.
...are you talking about the ornamentation? Google "Dentil" if you want to learn more about what you're modeling/building. The other molding can be done with Sweeps, such as Wall Sweep, Slab Edge, Roof Gutter, Roof Fascia, etc.
FWIW: I'm certain you can find a Dentil Line-Based Revit Family on-line as well.
