A system that looks at the various aspects of condition and presentation with a number/letter scale might be more flexible.
Something like….
Condition of Lock, Key(s)and Hardware each graded as below.
A+(absolutely as new)
A (light storage marks)
B (signs of wear)
C (light scratches/light corrosion)
D (heavy scratches/heavy corrosion)
E (battered/gouged/worn)
F (very poor)
N (not present)
Completeness
W (complete with all original accessories/instructions)
X (oem key(s))
Y (pattern key(s))
Z (incomplete)
Condition of Packaging
A+(absolutely as new)
A (light storage marks)
B (rubbing/creasing/light price markings)
C (slight damage)
D (heavier damage)
E (battered/dirty/heavy pen marks )
F (very poor)
Presented as:-
<Lock/set condition><Complete?><Key type><Condition><Packaging condition><complete?>
Examples:-
DZN = Tatty lock has missing parts and no key
CXB = Lock has light scratches and/or corrosion and oem key with signs of wear.
EYE = Lock has seen a bit of life! so has the non original key.
A+XAWB = Brand new lock,keys and hasp etc. in slightly grubby box.
This scheme needs refinement and will never cover all cases but might do the job?