I just bought a used k3 from a guy at our track for $575. He is the fastest guy at the track, and has only had the car for 6 months. He's meticulous, and it had many extras.
Racers edge braces, k factor hinge pins, all new fresh bearings, diffs, and shocks. And a large zip lock bag full of spares. Along with one airtronics 94358z servo.
I'll be keeping this one around, and going with either the x-ray, or the 777 next season.
Brandon