Just your typical used vehicle salesmen. When I was new to the world of motorcycles they took me for a ride (pun intended) and I ended up paying almost $4,000 grand for a 2005 Yamaha V-Star 650 with approximately 25,000 miles on it. Which has a going rate of anywhere between $2,500 - $3,000 on any Craig's List type forum.
The bike had an old battery which I had to replace ($200) and also was leaking fluid from the fork. All of this was apparently not discovered during their standard "enter number here" point inspection.
Now that I'm older and wiser I can say with confidence that Craig's List or EBay is a much much much much more financially beneficial way to purchase a used bike.