My favorite place to pick up extra parts on the fly... If you are getting keys copied though, do be careful. I would not hold the blame to cottins for bad key copies. Different key manufactures for the same key blanks will have different backstops on the bottom of the key blank which would throw off any copies you have made. Just make sure and check your key cuts before you leave because sometimes they need to eyeball the key to be cut for proper spacing instead of using the machine. Same goes for most hardware stores though, unless somebody knows better.