https://www.npr.org/2022/07/19/1111765630/on-demand-shuttles...
15 minivans replaced 6 busses, at a cost of 1.6 million to 1.3 million per year - but with much better coverage than the busses.
Of course this equation will look very different in big cities where economies of scale from mass transit kick in, but hey, small cities need transit too.