It must fit on my shoulder, it should be a soft, quality leather (though I've been known to buy fabric bags on occasion) and it must be either truly classic, or completely unusual. I don't like buying trendy bags- rather, I try to buy things I can use for years. And that will last that long. I will, on the spur of the moment, buy a "trendy" bag, but I've never spent more than $100 on one.