I don't think the cost will be different for a consumer car or a fleet car. I'm just saying the cost will be pretty big, and for consumers the value you get is "I can relax while driving" (not worth very much), while for cab companies the value is "we don't need to hire any cab drivers" (can easily be worth $100 000 per car over five years).
Sensor suite, software licensing, and data licensing. If solid state lidar can get there soon enough, that will help. Data licensing for extremely accurate data for everything - traffic lights, stop signs, every single intersection, etc.