Since I find myself typing out the same thing every time I send a commission request to someone, I thought I should list some of the conditions I require from the artists I commission, and what things I need to know

I need examples of each kind of commission, usually I'll ask for sketches
I need to know how much it is per extra character and how many characters come with a sketch (some people I've come across offer a flat price for sketches as long as there aren't too mny characters)
If it's not a personal piece then I need to make sure if it's alright with you if I can use the commission as an illustration in my novel provided I give credit (probably the most important one )
I need to know about your current worklod, like how many commissions you're currently doing, if you have a wait list, and your average work times just so I can get a good idea (I try to avoid artists who take too long since I get anxious easily )
If you have AIM I'll usually say hi and talk with you, and every few days or conversations I'll ask about your progress, however don't stress since if you hven't dne anything I won't press it. However if it's taking much longer than we both anticipated then I'll tell you if I'm becoming concerned.
Finally it's really important I see a draft sketch first as my characters are very stylized, I find that making them too realistic can take away some of their expression. Also it's a good idea if you observe my previous commissions so you have an idea of the bodily proportions I'm after - something between animalistic and humanoid (like big hands and feet, short arms and legs, rather large heads with expressive faces)

I think that's all I can think of at the moment but if there's anything else I'll add it here