The Basics: Hand drawn sketches are $2 (Colored with paint and inked will be $5 extra as well as a background)
Digital art is $5 (w/ color is an additional $2 and shading/effects is $3 extra) (Adding a background will add an additional $5 and full body is $5) (Adding more then one character is $7 each)
Other Options: iPhone/Android wallpapers are $15 each; PC/Mac wallpapers are $20 each.
Badges are $10 each and with your choice of digital or traditional on any amount you please.
Stickers are $5 each and same scenario with badges.
Reference sheets for your unique characters are $20 each.