Here are my same four main options for commissions but now with some links to examples of what you would be getting.
A: Cleaned up sketch of single character: $10
B: Inked drawing of single character: $20
C: Inked, colored and shaded drawing of single character: $30
D: Character reference sheet, including 2 poses: front and back and arousal closeup $40 $50 for more details and shading
And here is how the options progress based on character count:
A with 2 characters: $15 B with 2 characters: $25
C with 2 characters: $35
C with 2 characters fully drawn and shown $40
A with 3 characters: $20 B with 3 characters: $30 C with 3 characters: $50
With all options alternate versions of the same picture; say a spooge ver alongside the initial non-spooge ver or a transparent version that doesn't require drastic additional work are free extras typically as such edits usually only require minor alterations. Of course this will often depend on a commission by commission basis.