Why would you part with money with out seeing or riding a motorcycle first ? the motorcycle trade is no different to the car trade.
I've bought a couple of bikes unseen, my SV650 from a small time dealer on eBay who had excellent feedback. I spoke to him on the phone, asked a few questions and he delivered it. The bike was actually even better than I was expecting, virtually showroom condition.
The second one was a GPZ500 for about £400, that was not taxed or MOT'd. Someone had attempted to paint the tank with some kind of mat black paint, but a couple of hours with wet and dry had it removed and the original paint was gleaming underneath. I used it for a year and tidied it up (serviced, new tyres, rebuilt caliper, powder coated swing arm etc.) and then sold it unseen for £800. A really nice lad from Lancashire came all the way down to Devon and couldn't believe how good it was.