I've always thought my car should have a cost meter on the dashboard. Most people, if they think about cost at all, just include fuel expense. If the meter included insurance, taxes, depreciation, maintenance, that single destination trip is going to be eye -popping, and the Uber fare won't seem so bad.
But it's the "freedom" of being able to hop in and go without an obvious incremental additional expense.
It would be easy for us to live with one car, but it ain't happening. For us, just not enough to be saved on transportation.
You can estimate cost-per-mile on Edmonds site, IIRC. But, of course, it's so dependent on a lot of variables. Each additional mile should actually cost a bit less as you are quickly (and then more slowly) absorbing the fixed costs.
Imagine that you buy a new car and a pool of 4 or 5 people use it constantly (not sure why, but bear with me.) If driving freeways/interstates, such a car could easily be driven 1200 miles/day. In one year, you would add as much as 400,000+ miles to the odometer. Because you would never age out anything (all the rubber - except tires and belts) would still be good in a year, for instance) so your costs would be (fixed: insurance and tags) and mileage proportional (fuel, maintenance, depreciation.)
Yeah, at years end, your new car is likely worn out and near worthless, but your cost per mile would be the very minimum possible.
More likely, you drive 3,000 to 20,000 miles/year. That makes a huge difference in cost per mile due to the fixed costs being divided by such a wide rage of miles. So the cost-per-mile calculation is problematic at best. In hind-sight, you could figure it but going forward, you'd need a lot of estimates.
Still, a good concept to understand what your car costs you vs Uber/cab/bus/bike etc. Of course, that's probably moot unless you can delete one car from your garage by using alternate transportation. Still, YMMV.