Gastly

Grading with PSA pays if your copy has better than a 16% chance of a 10.

28% of the 89 copies PSA has graded got a 10. People mostly send their cleanest copies, so a typical raw copy's odds are lower.

Raw (NM)

$17.51

TCGplayer

PSA 10

$402.00

7 sales

PSA 9

$58.50

11 sales

If it misses

$39.29

below 10, by PSA's grades