Complex character charge

Character Level Details 
Your standard simple human / furry/ monster girl character with max 3 skin / fur tones.No Extra Charge
More than 3 skin tones, intricate patterns or tattoos, complex big hair, large wings, feathers, extra heads, multiple limbs, multiple tails characters that make me have to render them uniquely for example slime girls, characters with clothing that features chains, frills, belts, zippers, lace, decals like patches on a jacket, characters with complex clothing, a lot of bodily fluids than normal wetness.Up to $30 or More on a case by case basis

Please note this is on a case by case basis. This is just a general guide, feel free to ask me any questions.How do I determine whether details are complex or not?
- If I have to do a lot of line art for the extra details
- If there are a lot of small intricate patterns and designs
- If it is something that will take me a long time to render out