I want to approach a few artists about doing a commission, but I'm not sure what would be reasonable to pay. I understand this depends a lot on what I want, but do things like style, detail, background and size all play into it?
What I'm wanting done is a military portrait, similar to this: http://www.1stmaw.marines.mil/portals/65/Site%20Images/Leaders/CO/VMFA121_CO_LtCol_Rusnok.jpg?ver=2017-02-06-182159-447
Only using the characters from my story, in the uniforms of their military, with their flags, etc... The uniforms are closer to flightsuits than anything else and the background is exactly the same picture to picture. For simplicity's sake, however, let's assume I only want the first one. (so the work the artist charges for to make the background is lumped in with the first picture only).
Does anyone here know what would be reasonable to offer for this? In the future, what should I consider when giving a price to barter from?
Are there any questions I should anticipate and try to answer in my listing (aside from character descriptions)?