All the local LQS I have been to are pretty generous. At my Joann's or HL I make it a point to say something about needing the full amount cause I am calculating it pretty close or something to that effect. It usually gets me a skosh over what I paid for. And also I always try to be extra nice to these people, I have worked in customer service and lots of these folks get treated miserably at times, so I think if you are really nice they want to be nice back.