The following sources were cited in SAP Digital Futures Issue 02: Where Will the Self-Driving Car Take Us?

The cost of adding self-driving technology to a vehicle: US$8K−$10K and dropping.
Alex Davies, “Turns Out the Hardware in Self-Driving Cars Is Pretty Cheap,” WIRED.com, April 22, 2015, http://www.wired.com/2015/04/cost-of-sensors-autonomous-cars/?mbid=social_twitter

Average savings in the U.S. alone: $1.3 trillion – 8% of the U.S. GDP.
Autonomous Cars: Self-Driving the New Auto Industry Paradigm, Morgan Stanley Research, November 6, 2013, http://orfe.princeton.edu/~alaink/SmartDrivingCars/PDFs/Nov2013MORGAN-STANLEY-BLUE-PAPER-AUTONOMOUS-CARS%EF%BC%9A-SELF-DRIVING-THE-NEW-AUTO-INDUSTRY-PARADIGM.pdf

The 1.2 billion cars on the roads are used just 4% of the time. That’s 8.2 trillion hours of nonuse per year.
Andrew Simonetti, “The Futurist – Uber, Take the Wheel,” The Daily, April 13, 2015, http://www.dailyuw.com/opinion/article_a3911e4a-e244-11e4-a1f7-8fbb1ff20a33.html

2020: fully autonomous cars arrive in dealerships.
“Everyone Will Have Self-Driving Car By 2026, Analyst Says,” The Huffington Post – Tech, February 28, 2014, http://www.huffingtonpost.com/2014/02/27/morgan-stanley-autonomous-cars-prediction_n_4867613.html

Software will make up as much as 40% of a car’s value.
Autonomous Cars: Self-Driving the New Auto Industry Paradigm, Morgan Stanley Research, November 6, 2013,
http://orfe.princeton.edu/~alaink/SmartDrivingCars/PDFs/Nov2013MORGAN-STANLEY-BLUE-PAPER-AUTONOMOUS-CARS%EF%BC%9A-SELF-DRIVING-THE-NEW-AUTO-INDUSTRY-PARADIGM.pdf