Marc,
You could use different Materials for each respective color entity (trim, sofit, etc.). So for example, let's say you start with the Material "Color_000" (that's just a standard white). Create a new material from it (see attached) and name it descriptively (i.e. trim). Create a new material like this for each item and name them descriptively. Now when you've completed your model and applied materials to the appropriate faces, you can just go back to your materials palette and make changes to the desired parts.
As far as using groups and components, I would recommend putting all of your trim into a group so it's easy to select just the trim if you want to (open the group and "select all"). That way, applying materials will be easy too.
[image: create_material.gif]