Incorporation - several companies under 1 incorporated name structure???

What you are describing is a holding company, which can be a corporation or a limited liability company. Under a typical structure, you would own all of the interest in the holding company. You would then form subsidiary companies (which again could be corporations or limited liability companies), and your holding company would own all of the interests in the subsidiary companies. Whenever setting up entities for multiple businesses, however, you should consult your accountant, as the ownership structure, type of entity, and tax elections can have a huge impact on the amount of taxes you pay. Good luck!