I don't know the exact "cost", which may be too complicated to calculate it, including car,maintenance,gas,insurrance, even tickets.... 1 O5 [/ A! N! i) J) e/ {( V! Y" R
For me, I think car-pool is just to share part of gas "cost" and have some fun on road.....* C$ ~; T# ]1 X, j% B7 f
/ F# Y0 I/ v. G( _. H% SI usally charge passager 30 bucks for a trip.