Starting miles: 77810
Ending miles: 94106
Because we drive less and don't get typical discounts of having two cars (e.g. multi-car discount on insurance) our cost per mile went up, but total costs are lower. This is largely because driving fewer miles causes fixed expenses (insurance) to weigh in more heavily against operating expenses (fuel). In 2011 (remember I realize this at the half year so 2011 is roughly June 2010-June-2011) we had two vehicles, drove 9,532 miles and incurred $4,262 in expenses. In 2012 we had one vehicle, drove 3,437 miles and incurred $2,863 in expenses.
Auto service varies wildly from year to year. 2010 was an unexpected A/C replacement and 2012 was 90k maintenance. I suspect we'll be buying new tires soon so maintenance will continue to remain high.
Insurance is about the same despite going from two cars to one car when I would have expected it to go up (in 2010 and 2011 we had two cars so I allocated 50% to the Honda). I suspect it's because rates are lower in Idaho.
Depreciation was sort of odd in 2011 as the car actually appreciated in value, I suspect that was a one-off adjustment in price due to gas prices or inflation or something so I expect it to remain around 400-500/year.
DMV registration is a lot cheaper in Idaho, about $30/year. We also haven't had to smog our vehicle which saves time and money (and also is better for the environment since you're not driving needlessly).