[ghaff]

And it's difficult to see how those ad hoc rentals can compete with a fleet management company that has economies of scale and optimizes for short-term rental. Car depreciation is more mileage-based than time-based so it's reasonable to assume that the rates people would get would tend to reach a point where they were pretty close to the cost--with perhaps an exception for times when there's extraordinary demand.

[RantyDave]

Yes and no. I can certainly agree on a theoretical basis, but the black cabs that have crawled around London since the 50's are privately owned and built to last.