I can tell you from my experience working in other industries that retail markups can run anywhere from 100 to 200% of cost. It sounds high, but you have to take into account, time, taxes, transportation costs, packaging, advertising and everything else that goes into the actual sale beside your time and materials. Make sure that you are making enough of a profit for yourself after you pay out consignment fees and anything else.
To start with, are you making enough on each item from your Etsy sales? I would start there. Don't underestimate yourself. You are an artist and if someone is willing to pay thousands for a designer bag they should be willing to pay a fair price for a handmade limited edition or one of a kind design from an up and coming artist. Market yourself as such and go for it!