Got my new blue M3P, looks and performs great. Not 3 weeks later, while stopped at a light, got hit pretty substantially from the rear. The back bumper shows damage, the underneath trim piece popped out and the sides of the bumper popped out a little from the rest of the body. The hit was low. No alerts or messages and the car drives fine. No visible damage to trunk door or operation or internally. Reported to insurance and I secured a time with the Tesla body shop in Boston. My question is, what additional damage might there be? I am trying to get a feel for how bad this will be but don't know much about these cars or what is back there. Is this a simple bumper and trim replacement or could it be really bad? I want to be effective in dealing with the insurance companies right from the start so any experiences or tips would be much appreciated.