The other reason I won't be pursuing that bike is that that there were photos of all parts of the bike except the left hand side. I had to rely on his assurances that the left hand side was every bit as good as the right hand side, but 10 photos uploaded and none of a particular part of the bike gives cause for concern.
I've bought the following off ebay over the last few years; RS50, NSR125, CBR125, ZXR400, ZZR600, GSXR600, CBR600F, and VFR800Fi, all without issue. I've also walked away from just as many.
What I have learned is to read as much into what isn't said or shown as to what is. To carefully check every photo, zooming in where possible, looking for accident damage/repairs, mismatched fairings, wrong parts for the year etc. To get the registration number before you go and waste a trip to see the bike so you can do a vehicle check and make sure its not stolen or written off. To check the sellers feedback to see what he has bought and sold recently.
What I am looking for is a feeling that the seller is honest, through their advert, description, history and communication, and that the bike is kosher. If something smells wrong I just pass on it, another bike will come along before long.
Also when comparing similar bikes make a note of how much it is going to cost to put on the road. Does it have tax/mot? Has it stood in a garage for 3 years, if so it is likely to need new tyres, the fuel system flushing, a new battery, fluids changed and brakes serviced? Will it need new tyres, chain, sprockets, brake pads soon? Is it due an expensive/time consuming valve service soon?