Since I haven't played riggers yet, I normally keep just one vehicle, as more is impossible to fit into the budget at start-up after everything else you need for those things you're supposed to be good at. I normally take a Comet or something similarly common, add a spoof chip, morhing licence plate and run-flat tires and that's about it. Sometimes a smuggler compartment to stash really illegal stuff while driving around, but not much more than that.
Except that one ex-combat biker chick I played once. She had a Contrail fitted with just about every accelation mod the GM let me have (and run-flats, and spoof chip,...). But in that group we also had a technomancer/face and a rigger, so we had all the vans and drones we needed.