I've been working with a new style, recently, and I'm... unfamiliar with Menewsha's currency.
What is an image like the one below worth, here? Yes, I realize it is uncolored, and that reduces its value.
Try to quote a lineart price, and a colored price, if you can muster the effort.

Click the preview for a fullsize image!

actually lovely the fact that its a nice clean lineart without colour doesnt detract at all from the price. you could easily charge a good 1k for half body with your lovely style. Its certainly completely different then any of the other artists currently accepting commissions on mene. Best way to see what people will pay is either slowly raise the price and see if your still getting the influx of interest you want? or.. do something along the lines of an offer system. where people put down the character they want drawn and the amount they are willing to pay for art of said character, that way you can pick and choose whatever most interests you. *shrugs* most of the avid art collectors on here are really lovely about tipping though. *shrugs* and there are certainly a big chunk of us on here.