I have had some good scores, and I think it comes down to reading between the lines. I usually score with people selling something they don't really know about and poor photos. I take a chance. Retina III Big C for < £50 in virtually mint and a virtually mint Ikon Nettar for £36 with original receipt, guarantee. This sellar was obviously "old school gent" because he even refunded a £1 postage (obviously unasked) because the actual postage was less than he had to pay!!! I had some email conversation with him afterwards and sent a couple of prints I had taken with the camera.