From SketchUp to final image.

I thought I'd post this image of my 3D SketchUp model, as exported directly from SketchUp, to illustrate how many more steps are required to turn a 3D model into a usable, marketable rendering.

As you can see, the modeling is merely one small step in the whole process, particularly for interior shots where you need lighting. SketchUp doesn't do lights except for the Sun, so unless you've got big windows and lots of them, you're not going to be very happy with outputs directly from SketchUp of interior views.
The final step in the process, is to work the image in Photoshop, to dodge/burn areas, and place additional vignette blurring - if desired - to add a touch of the toy camera look to images...stylize the image to bring some additional eye candy.