2012 GL 350 Seized Engine: Help Please!
 

I have a 2012 GL350 which I bought back in March. I've thoroughly enjoyed driving it until the engine died on a highway. I had the vehicle towed to MB of Hunt Valley in Maryland. I was informed the engine had seized, could not be manually started and could not be serviced. I was quoted 15K for a used engine and 4.5K to install it. Obviously that's more than what I paid for the vehicle. I'm planning on getting another opinion from a local shop. Before I do I was wondering if anyone could offer any advice here. Has anyone had this issue? Have you replaced a motor before and if so what was the cost? Should I just write this off as a very expensive lesson? I'd be very grateful for any guidance. Thank you!!!!