It must be free of major chips, cracks, or bends. While tiny nicks (under 1mm) can be honed out, doing so reduces the blade's width and lifespan.
While scales can be replaced, original ones in good condition add value. how to buy a vintage straight razor
Avoid blades with rust or deep "pitting" (small holes eaten into the steel) on or near the cutting edge. As a rule of thumb, the blade should be clear of rust at least 3mm above the edge to allow for future sharpenings. It must be free of major chips, cracks, or bends
The blade should be straight and not "warped" or "smiling" excessively (unless it was designed with a curved edge). 2. Inspecting the Scales (Handles) how to buy a vintage straight razor