I don't know the exact "cost", which may be too complicated to calculate it, including car,maintenance,gas,insurrance, even tickets.... % [8 G- z4 b0 z; u. i8 }9 x; L0 P1 C) |1 j v+ {9 U/ E
For me, I think car-pool is just to share part of gas "cost" and have some fun on road..... % P- j9 h! Q) Z, m2 `- R1 ?/ M& a, R9 }" A; [. f- e
I usally charge passager 30 bucks for a trip.