Well, it's roughly something like this:
1. One character with no background: 60$. With background: 65$
2. Two characters with no background: 70$. With background: 80$
3. Three characters with no background 90$ With background 100$
Adding colors adds 30$ to the price, and of course if the pic has more people and a lot going on, the payment will vary.
It usually takes about two weeks to finish a commissioned drawing. You can contact me easiest by E-mail: email@example.com
Let me know what you have in mind!