There are multiple factors that can be used in order to create multiple looks and feelings for photography portraits using one location.
  Location This would be the simplest option but may not give you the best results.
Using a indoor natural setting such as a living room with large north facing windows, could give you a better look.
Choosing an outdoor location would be preferable because you can use a combination of the natural light along with the location, will allow you to come up with a lot of different, natural looks.
 Look for a location with good variety such as a park with lots of trees, a city background, or a field with a lake nearby, are great example of a good location to look for.
Find a place with both shaded areas as well as direct sunlight.
  Lighting Here is where you will really be able to create a unique look.
Photographers often bring off camera lights to overpower the sun.
This allows you the flexibility to be able to photograph anywhere.
You can place your subject with their back facing the sun while using an off camera light as a key light.
You can also place your subject in shade for soft even light distribution.
You can overpower the ambient light easily when using off camera lighting to create a lot of detail in the background.
Dial the ambient light up and use the flash as a fill light to quickly create a high key portrait.
Posting Be sure to get a good mix of far away, medium and close up images if your subject to create a good amount of variety in the images.
Try different poses like romantic, traditional and fun poses to really stand out.
Lens selection Your lens selection can have a high impact of the way your image looks.
You can have the background nice and sharp or throw it completely out of focus to get two separate looks.
Post production Using software such as Photoshop, Aperture or Lightroom, can have a huge impact on the final images.
Try using black and white to create a unique look.
Using a warm vintage tone is also a very popular way to change the mood of your image.
As long as you take into consideration these key principles you will be able to create dynamic portraits that have multiple looks and feelings.
Of course it is always up to the photographer to come up with unique and creative ideas.