Pre-owned Explorer Sale

I'd used Gedge before on a used sale, so should have known better when I bought a Sprint GT from them which had an inherent gear shift issue which they failed to address.
So back I went for another try; they had a high miler Explorer available, but all the dealer service stamps were present (from KS Gedge) so presumed it would be a solid bike.
The experience didn't start well when they reinstalled my Garmin Sat-Nav wrong within days and then when I asked them to check the front brakes - as I'd experienced some shudder and pulsing from them - I was told there wasn't a problem and this was just something I would have to get used to from a Adventure Tourer MC.
Well some second opinions resulted in the diagnosis that the headstock bearings had failed and the front discs were warped, though as this was now outside the 3 month warranted period and 'serviceable items' I had no form of recourse for the £500+ bill I am now left with; interesting that they had completed all the previous servicing and put an MOT on the bike when I bought it which should never have been certified or at least an 'advice' to check the brakes.
Lesson now learnt, not going back to them for anything, not even a T-shirt:-(