there are a bunch of threads on the topic, it's easier to do a search.
the general frame of mind is that you can charge what you think people will pay. most start at $15-20 and move up from there. i'm not sure what you mean by a commission, since the buyer pays here and gets a print. if it doesn't show for sale, it won't show in the search. usually the best way to do it is - note the retail price without a markup, and look at the recently sold page. look for people that sell all the time that have similar work and see what they are charging. keeping in mind that i think it's 10% higher since Faa takes a cut as well.
looking at your images - i can't see them up close, but the few i looked at, may have printing issues. your images should be large without stretching. be clean, free of noise, not blurry, or blocky. quality wise some are ok, but others probably not. but i can't tell by looking at those samples. you can always upload and do a bulk change later on if you want. if you uploaded an image, you didn't hit submit because i don't see it in there.
---Mike Savad
