Walk in a store, look at the salesman, hold up your checkbook and say, “The full amount for what I want is right here. Only you can mess this up.”
Oh ok, be nice about it, but remember their game is to get you to pay as much as possible for what you want. You may want to let the salesman know you're playing your own game -- to pay as little as possible for what you want.
Then you can both go from there . . .or not.