I negotiate everything. I think I embarrass my husband sometimes. 80% of the time they will negotiate. You have to be willing to hear the word "no," and decide ahead of time what you are going to do. I usually take my business elsewhere, unless it is something I cannot live without.
Also, with big stores, you can negotiate more on floor samples finding flaws, etc. The managers don't normally care because they are not attached to the stuff. Small businesses, you negotiate opposite. Let them know that you love their store or the piece but be super nice and tell them what you can afford.