Note that CARMAX offers trade-in value and is always better than the dealer in this regard in my opinion. Of course, private sale should always yield more...low-to-mid 30s sounds about right. Your car looks fabulous by the way!
Currently: 2015 Porsche 911 GTS and 2016 Cayenne S eHybrid
Past BMWs: `05 645CiC; `07 650i; `08 M6 convertible; '08 135i; `11 750ix MSport; `15 M235i convertible
Others: '11 Panamera 4S; '13 Boxster S; '13 911 C4
"You think that's air you're breathing now?"