The IBM 5110 Type 1 that I have was ordered and used by the Stone Perforating Company in Chicago, Illinois in 1979. The equipment includes the typical set of IBM manuals, but there is also a letter included from IBM Marketing Manager Steve Crook to the Stone Perforating Company President, Lloyd Stone.
Companies had the option of leasing IBM equipment. In this case, the equipment was “installed on a purchase basis” and “designated as customer set-up.” So, the letter refers to a bulletin that describes the expectations that the customer must perform for that setup. In addition, the letter references an Investment Tax Credit (ITC), which a company could use to help offset the cost of the equipment.