Architectural rendering can be created for both the interior and exterior parts of the building. That means renders' knowledge of how a building should look in real life is not restricted to any specific parts of the structure but the entire building.
The lack of the understanding of the decorating skills of the renderer can have adverse effects on the sales of the project. There are huge chances of its being a disaster or failure if it falls short of expressiveness.
Exterior rendering should also imitate photo realistic visuals or images. The major concentration in exterior rendering is given on the natural elements such as creating flower pots in the lawn, creating a turf in the exteriors, along with right lighting effects and an expressive sky etc. Find more details about exterior rendering through https://www.empirerender.com/3d-exterior-rendering/.
While doing the interior rendering of a building a renderer should be fully aware or wise enough to choose what to add in the room and what to leave. He shouldn't be giving any chance to the clients to raise doubts on his taste.
In interior architectural rendering the images of interiors should look like the original photos taken from an existing building.
That is achieved by creating original looking elements in the room such as the room colors should be defined or added according to the rest of the objects present in the room or time of the day. That means the lighting effects are also very crucial.
Other things that should be given prominence are shadow effects, object creation such as paintings hanging on the walls, photo frames kept on the side table and a single stool kept on one of the corners of the room etc.