i try to determine what the customer base will accept... if you are in an area with well-to-do folks who normally pay $50-$100 for a purse, you will be able to sell your items for a decent amount (materials x 3 is a normal base)these folks tend to not buy if items are (cheap, but will pay if priced a bit more) but if the customers are more in line with retired, lower income (or fixed income) they may not be able to pay those prices and you would do better to keep everything $20 and less...and figure the items that are under $10 are going to sell the best. location really does matter regardless of whether or not its a regular store or a craft fair.