yeah, something like that could work...or 0-10 scores could be entered for each of the following categories that could have weights (maybe 1 for pcb, cab, art, monitor and .84 for the rest) - (yeah..i've put some thought into this and maybe i'm overthinking it

):
in the end they are all subjective anyway
PCB
-Does the game boot up and run?
*if no sound, use sound section below
Cabinet Structure/Basics
-water damage?
-Edges/corners cracked?
-dings/dents/cracks/excessively drilled holes?
-leg levelers/wheels in good shape
-t-molding condition
Side/Kickplate/other Art
-Condition/Accuracy of paint job or decals
Monitor
-exists and powers up?
-all colors firing?
-bright enough?
-picture displays correctly/geometrically accurate?
-does it have burn-in?
Glass and Plastic Bezel
-scratches in the glass?
-artwork flaking?
-plastic bezel exists and in good shape?
Control panel overlay
-is it all intact?
-is it clean?
Marquee
-scratches or graffitti?
-artwork still in tact?
-any warpage?
Internal Wiring/Electronics/lighting
-All wiring in place?
-all components exist (fuses, power supply, etc..)
-does the lighting behind the marquee work?
-coin door lights work?
Controls
-buttons/controls exist and work?
Sound
-does the sound work?
-speaker in good condition?
Coin Door
-rust?
-mech(s) are in place?
-lights (if applicable) exist and work?
-coin bucket in place?
-when you put in a quarter, does it register?