Just happened to me last week in my E70. Woman turned around to tend to her granddaughter in the back seat and basically drove into me. Her Altima was totaled. Don't know how fast she was going but I'd guess greater than 20 mph. Knocked my glasses off, I was surprised how much my back actually hurt-seems okay now. Lower tailgate panel and plastic bumper will have to be replaced, the parking sensors no longer work. Her insurance company will have an appraiser look at it tomorrow. Have not had a chance to get it appraised. My damage as well as OP's does not in my opinion fall into the realm of reducing the value ( especially mine with 131k miles) but be aware that more damage could impact trade-in/resale and in that case, one may want to negotiate for diminished value.