with everything mine is $766.28/mo, $9195/yr.
but putting in car note and insurance doesn't make sense unless you use this particular car ONLY for work.. So depending on how much your commute mileage is compared to your total mileage.. that can change. mine is about half and half.
so just gas and tolls:
53 miles commute round trip, 26 mpg calculated avg, ~2 gallons a day, ~$100 in gas for 20 day work month.
Tolls, I use 3.60 ea. way, so $144 a month.. $244 total.
however, to work i almost always exit i-10 feeder, since the BW8 feeder road goes over I-10 now w/o a light, and I'll ride the feeder to westheimer, that saves me $26 a month skipping westhmr. plaza, and on the way home, I typically ride feeder all the way until after 290, skipping westhmr and 290 plazas, saving me another $52 a month..
By doing that alt. route, I knock off $78 a month in tolls, bringing me down to $168 for gas and tolls.
But in reality, I vanpool, and I pay about $80 a month, plus the gas to our meeting place which is 8 miles round trip so that adds on another $15 a month.