> For modern cars, maintenance is not a significant expense compared to the purchase price and fuel
Its certainly not in the first few years (which is why some companies offer prepaid routine maintenance) -- in the latter several years of a 10 year life, that's far less the case.
> No need to buy new, let some other sucker eat the depreciation. A 3-4 year old Corolla (or equivalent) shouldn't cost more than $10k.
A 3-4 year old Corolla or other economy car is going to be spending more of the 10 year life you propose in the part of its lifespan where the "maintenance is not a significant expense compared to the purchase price and fuel" argument is invalid than a new car.
> Inflation isn't going to be a significant factor, since long-term savings are going to be placed in something like a TIPS bond.
A TIPS bond is indexed to general inflation, inflation of higher education costs has been much higher than the general inflation for quite a long time. So, yes, for college savings, inflation is likely to be significant factor, even if you use an investment vehicle protected against general inflation.
> It is possible that the total cost will increase, but what are the chances it'll cost more for a regular school then than it does for a top-tier school now?
Quite good. Using reference points I'm familiar with, the tuition for a UC now are higher than the tuition at Caltech in the early 1990s, and the ratio of college tuition inflation to general inflation has been higher in the second half of that interval at the first, having stabilized at around 2.0 from the late 1990s on, where it had been at around 1.5 in the early 1990s. So