"First post! Also, does teh description have to be written, or can it be a picture? Or could it be a picture as the base with descriptice writings about mods, extras and so on?" 

I prefer a written description and a picture. Although a reference that openly explains the character can bar this. This helps us ascertain what the character looks like in our head, and if there's a physical difference from the ref to the description: We will spot it.