If I do such kind of business, I will charge at least 10/day.
Sample:
One deliver will cost about 30 min(2 min in heating the car, 10 min on road to passenger, 10 -15 min on road to passenger's work place and back home.)
So pickup also cost about 30 min.
Gasoline cost is about 4 lites at least for 1 hour, my car is 6-7 lites for 1 hour. counted as money is 2.8 - 4.9 per passenger.
Labour costs at least 7 dollars per hour in Ontario I guess.
so total is about 10 dollars per person per day.