>spending tens (hundreds?) of thousands of $ on apparently unserviceable cars, then opening up the high voltage systems on them with no help from the manufactur

>spending tens (hundreds?) of thousands of $ on apparently unserviceable cars, then opening up the high voltage systems on them with no help from the manufacturer. Once you get to the level at which you're comfortable working on any one of the subsystems alone there's a snowball effect. Rebuilding a flooded car isn't fundamentally harder than any individual repair. It's just a bigger job. It's mostly a question of available resources (space and cash flow being the two most common bottlenecks) and motivation.