Lineart (one character) = $5 (USD)
Basic colour (one character) = $10 (USD)
Detail colour (one character) = $15 (USD)
Full detail painting (one character) = $25 (USD)

+ a character = $5 (USD)
+ simple background = $5 (USD)
+ complicated background = $10 - $20 (USD)(depends on how complicated and which style of colour)