C1 = As new / excellent / well looked after / very low use
C2 = Very good condition / looked-after runner / possibly a professional-quality repaint, modifications, detailing
C3 = Heavily modified / subjective repaint, detailing / heavily used but running / poor or non-runners
NB: Any non-runners will be stated as such in their descriptions, and classed as condition 3. All items should be considered unboxed unless stated otherwise in their description