I try to charge a fair price and still make enough for the time I put into the work...I also don't do any big projects for anyone as I know the cost would be far more than most would be willing to pay.
I used to work at a quilt store years ago and the owner did consignments with people who wanted to sell their work. We always got people coming in admiring the quilts, however, no one wanted to pay the price, especially when they could go to Wal-Mart and buy a quilt for $20...lol...
I only do scarves, hats, wristwarmers, cell phone cases, and the likes...I do the smaller things that I can finish quickly and charge less for. I sell my hats for roughly $30, however, if someone buys more than one hat at a time, I'll knock off a few bucks for them. I only charge about $20 for the scarves, even though they take more time than the hats, because even I wouldn't be willing to pay more than $20 for a scarf...well, unless it was one bad a** scarf! LOL The cell cases and wrist warmers, anywhere between $10 and $15.
I'm probably cutting myself a bit short with my work, however, the hats I do have been taking off like wildfire! I figure I'll get more charging a fair price and getting a lot of 'business' than I would charging more and having less people to buy them.
So far, between the hats and cell cases I've done, I've made over $200.
It really depends on you though, what you feel is a fair price for your work, the materials, and, whether you're doing it because you need the money, or, doing it more as a favor. We've gotten to the point where selling my work has become a necessity which is also another reason I stick to smaller projects. I don't want to get too burned out...lol