I have a theory that your best sales tool is your personality. If you project a glum, grumpy exterior then no one will touch you with a barge pole. People are people and will warm to someone that's pleasant to be around, open and friendly. You want to be the one they come back to when they've finishing traipsing around looking for the best bargain? Then be helpful, not skulking around like a shoplifter hoping no one speaks to you as we've all seen some do in various retailers. It's not always price that makes the sale.