Hi Mr Bankes
My best, and so far only used camera gear purchase is also a 20D and 17-85 lens, the seller listed the body as faulty, but I had my suspicion it would be the lens, having just paid to have another 17-85 fixed. What is more, I only paid £50 for body, lens, battery, discs, charger and manual in a fairly useless bag, £10 more than the repair on my other lens.
I really like the body as a near zero value item of great worth to me as a tool I can use in the less than ideal conditions of an auto workshop, I still treat it with respect, but it is not my high $ 7D if something untoward should befall it!
Best of all I like the lens as I was able to dismantle it, replace the ribbon cable and reassemble it to fully working condition, which gives a sense of achievement. As a point that may perhaps interest some others here, the ribbon was completely severed in two, yet when zoomed out the ends would make sufficient contact for the iris to work stopped down without throwing out an error.
I think this lens should have been eligible for a free repair by Canon as it was clearly a manufacturing defect, the cable guide was so bent in that it was pressing the loop in the ribbon together, causing a fold at minimum zoom rather than a smooth loop. £3 ribbon and a couple of hours time to have the kit working!
I just purchased my second Canon Eos 20D. I'm amazed that such a great piece of kit sells for such a cheap price. I've roughly decided on the Sigma 17-50 2.8 OS as my next lens and together with my telephoto lenses I think I'll be pleased with my kit. I think it's amazing how I can get two semi pro / enthusiast bodies for the price of one 1100D. I guess cameras are like that though. Whats one of your best used camera purchases?