Shopping for price works if you are looking for a physical item like a car at three or four different dealerships. If you are pricing a service
From the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) Journal Vol. 48, Nov. 2006
Whenever I think about roof rescues, the words “simple,” "efficient,” and “rapid” hardly ever come to mind. In general, there are too many variables on most roofs for an elevated rescue operation
