I don't know the exact "cost", which may be too complicated to calculate it, including car,maintenance,gas,insurrance, even tickets.... " O5 u# d* I5 G: K7 Z6 e! B3 u4 r; X0 k+ R
For me, I think car-pool is just to share part of gas "cost" and have some fun on road..... 2 c+ l( d9 V& D T # c b, o! \' h8 D4 gI usally charge passager 30 bucks for a trip.