Ned Chapin, An Introduction to Automatic Computers(1963):
Buying the stripped-down model is like buying a semifinished house; before you can live in it to comfort, you have to finish the interior work and supply the furnishings. To make effective use of such a computer you must acquire a substantial amount of additional storage equipment, a substantial amount of additional input-output equipment, and some input-output conversion equipment. Often the cost of such optional equipment will run to more than the cost of the basic computer. For example, the quoted base price for the Circle computer was about $57,000, but did not include the optional storage capacity (about $21,000), ten optional magnetic tape units (about $78,250), an optional paper tape reader (about $3100), and optional card input-output equipment (at least $5100). Although the quoted price for the computer was only about $57,000, the cost of the optional equipment came to an additional $107,450. To this would have to be added the price of the input preparation equipment and of any communication equipment. This could easily total more than an additional $100,000, (p.441).
IBM 7090; lease cost per month $65,000; the first large transistorized computer system to be delivered commercially. American Airlines used two 7090s to implament on-line reservation system in 1964.
IBM 1401(1960); lease cost per month $5000; the Southern Railway did its revenue and accounting work on an IBM 705, with two 1401s doing peripheral processing.
IBM 702(1955); lease cost per month $26,000; Chrysler used a 702 primarily to keep track of spare parts but also for vibration analysis in designing new cars. Prudential's applications, maintaining life insurance policy files, actuarial calculations. General Electric, inventory control, design of turbine generators, (Fisher, IBMp. 18).