In response to skipr:
Maybe my previous post will illustrate for you the challenges of residential service. As a commercial/industrial contractor, you may call a supplier for $10,000 in materials which they will ship to your jobsite. You may have a Purchase Order, material takeoff, and a phone call involved in this. You may also have material handling on the jobsite.
Your 30% may be much more profitable than someone in residential service trying to recover the time of a low-cost special-order item.
Dave
