I don't know the exact "cost", which may be too complicated to calculate it, including car,maintenance,gas,insurrance, even tickets.... 3 I B+ V3 E8 U# u0 D& U ! r6 |9 W/ x5 q1 u- F* qFor me, I think car-pool is just to share part of gas "cost" and have some fun on road..... 8 X2 ], e) W! P0 K+ b # m: U3 F: V' \4 yI usally charge passager 30 bucks for a trip.