I work 50/50, after the sketch is approved i get 50% of the payment, then once the work is finished i'll let you know to get the other 50% and then deliver the piece.
You get up to 3 small changes to the sketch for free if you changed your mind about something, after that i'll charge for each change, and once the piece is fully finished i won't change it again.
I DO NSFW in any of my slots.