Worth Grading
Grading Mr. Mime #11 from Detective Pikachu should cover its own fees comfortably. Raw copies trade around $2.98 while PSA 10s sell for about $216.18, a 133% Return on Grading. Condition still decides the outcome, so only send copies you'd back for a 10.
Among the 17 cards in Detective Pikachu with PSA 10 sale data, Mr. Mime ranks 9th for Return on Grading and 9th by PSA 10 price. Of the 5 Rare cards with PSA 10 sales, it is 4th for Return on Grading. The median PSA 10 in this set sells for $216.18. 11 of the 17 clear a 100% Return on Grading.