I want a user of company A see the website in the corporate ID of company A. Another user with outer skin and so on. Up to 3 or 4 contractors.

thanx

No I have a skin called Company, installed as a site skin and e.g. a skin called company b, and I want to have all the sites displayed with skin of my company as default if certain users from a contractor from company b log in they should see the whole site as if the site belong to their company with skin company b.

To state it clear:

I work for an architectural company and have a extranet with plans downloadable for users from contractors of a minaral oil company, i want to display our corporate design to normal users i create for our company and want a skin for the contractors of the minaral oil company get displayed the whole site as if it is their ID.

I am quite new to dnn and want to try it out, if we buy pro version to do this. Have quite a lot xperience in joomla or drupal. In drupal there is a possibility to set a default site theme to each user... and I am searching for a way to do this with dnn the best way.