I purchased mine at end July this year. A Luxury in white (colour I wanted), 65 plate, 20k miles, standard spec + sunroof (again I wanted this). Standard nav and no convenience pack (I find the NX one to be too slow anyway).
The spec on this one seems good. ML and premium nav. Best to check price against every other Luxury for that year on the approved used site. This should show whether it is a good price or not. The wheels don’t look like the standard NX Luxury wheels for that vintage.
Make sure they check service history - every 10k miles or 12 months whichever comes first. Ask the dealership to print out the service record.
Hope it goes well.