

Reasons not to TOAL from the roof of a car
The metal of the car seemed to interfere with the magnetic field and so the drone wouldn't land. Then it freaked out and ended up landing on the floor, a very rocky floor.
If I'd taken off from the ground the fall would have been much shallower.
The scratches on the top lens aren't super noticeable in most footage shot afterwards so I'll hold off replacing the lens for the moment.
The cracked glass of the sensor is a bit of a worry though. Not sure how good the object avoidance will be now and if it'll be getting freaked out over nothing instead.