deciding/Looking to buy 15-17 f06 m6 gran coupe

[FrozenRedM6]

Whats up everyone, new to this forum and was looking for some help. Can anyone tell me what the big differences are in the m6 gc from the years 15-17? I have been looking to buy 1 for the past month and half but cannot find the right 1 for me.
I am looking for 1 that is fully loaded comp package with orange interior. Exterior color does not matter as i will be getting it wrapped. Also this will be my first used car that I will be buying so are there any tips and things I should look out for?
If any1 is selling or finds 1 with low miles please send a link.

Thanks