First, welcome to the forum. It was a fun car for 6 years, first a 2014, then a 2017.
Second, don't know where you are but $16k sounds negotiable to me. Be sure to have the car checked out by a MB dealer before you buy to see if all required service was done and to let you know how much degradation of the battery pack has occurred. I miss the car.
Just leased a GLC300 to bridge to a future MB EV. Almost bite on a 2021 GLC350e last year but couldn't pull the trigger during covid when I wasn't driving much. The EQC is not sold in the US or I would be driving that. Yeah, the Burmeister is nice. I listened today for my 3 hour drive by myself. Very nice indeed.
Jeff in NYC
MB '21 GLC300; MB '06 E500W; MB '81 380SL
Retired: MB '17 B250e; MB '14 Be