Limits on cheap commissions

[laurenashleyart.livejournal.com]

Hi everyone! Thank you all so much for your previous comments and advice about shipment, your advice was incredibly helpful, as the options I had could mesh with their own, they got the suit in time!

Though I have a new question- How many edits/revisions do you allow cheap/sale commissions?

I'm offering a sale on full-color, full-body, shaded pin-ups for 10$. These at their simplest take me 3 hours to make. 10/3= 3.30$ an hour. I'm offering them as an anatomy study series.

However I have no ideas what limits to apply to these, concerning edits and revisions. What do you guys think would be acceptable limits for me to set for myself, and the commissioner?

Thank you guys so much for all your input, and thoughts. It really does help!