Uber Technologies provides a smartphone application that connects drivers and riders in 80 countries. Uber drivers are independent contractors using their personal vehicles; Uber Technologies has no vehicle fleet, no driver employees, and no face-to-face interaction with riders. Square provides credit-card readers and applications to make iOS and Android devices mobile points of sale. Square's reader is thumb-size and mailed to customers. Both of these companies have their headquarters in 1455 Market Street in San Francisco, which is very expensive commercial real estate. Describe three economic benefits to these companies of operating in downtown San Francisco as opposed to other US cities