I began to work in the world of 3-D modeling. Of course Since I have not been doing it long I have so much to learn. One of the quick tips I found to make my models look more complete is to add other modeled elements. For example since I work mainly on designing Trade Show booths I find my booths look rather empty, and to model all kinds of addition elements to give it that polished touch would take quite a bit of time. A great resources I use is http://archive3d.net/.
They have so many great items to give your rendering that extra polished touch.
Check it out!