I just let them know they won't have a sale unless I get some sort of discount. Either I feign disinterest or I'm more blatant about it (depends on the situation).
It's obviously much easier if you're buying more than one item, especially if one of the items has a good mark-up (TV, mp3 player, DAB radio).
It's obviously much easier if you're buying more than one item, especially if one of the items has a good mark-up (TV, mp3 player, DAB radio).