As
Cata1yst said, the best solution is to make hours+material costs, and checking out if it matches similar items in other sites.
Make sure to not make it too pricey for a start, to try to get a name out there. As soon as she gets some attention and some demand, she might consider increasing a little bit at a time
Try to make her publicize her art: friends of friends of friends might be very interested

The internet is a wonderful thing ^^