[chc]

My insurance costs haven't changed much based on my commute. Oil changes can be amortized to about $12 a month. We're still not anywhere on the same planet as the $700 figure. If wear and tear are adding up to $600 a month when you're only driving 45 miles a day, it sounds like your car is effectively dead and needs to be replaced.

[wtbob]

How much did your car cost, including financing? How long will you have it? What will you sell it or trade it in for? You can't forget those costs.

[chc]

You can forget those costs, because I'm talking about the difference between my car sitting in the driveway except for weekend trips and my car driving 45 miles per day. That cost is the same in either case, so it doesn't matter to the comparison.