At some stage or another, we've all traded / sold a bike on that's a pain in the arse. If someone on here can save you from buying that pain in the arse then all's the better as far as I'm concerned.
I'm actually surprised the question doesn't come up on here more often!
Wel, I've bought the bugger anyway! It is at a dealer and tbh I've traded in my 800GS with even less miles on it ...
For what it's worth (and if it was your bike) it's a 1200GS TE reg number KN13 FWF. It all looks good, just over 7k on the clock and I get a years warranty etc. My last air cooled 1200GS had nearly 13K when I traded it in and I had no problems with that.