How to model the ventilation system for baseline model.

Hello, I would just like to ask regarding how I should model the ventilation system of my baseline model. My project is a hotel building which uses chilled water as its main cooling medium. The primary cooling units are fan-coil units installed in each zone of the building. These FCUs only provide the cooling supply air needed to cool the zones to their respective setpoints. To introduce fresh air in each zone, there is a separate fresh air handling unit (FAHU). The fresh air that is introduced in the zones is pre-cooled by chilled water cooling coils before being introduced into the zones. Now, my baseline system is System 2 (Packaged Terminal Heat Pump). The main cooling type for this system is direct expansion. My question now is how should I model the ventilation system for my baseline model. Should I provide a separate fresh air handling unit (FAHU) in my baseline model to introduce ventilation air to my zones? Should I provide pre-cooling to this ventilation air before it can be introduced to the zones. And if this is the case, what should be the cooling type for this FAHU: direct expansion or chilled water (just like in the proposed)?