If you don’t haggle, you will pay about twice as much for your mattress as you should. No exaggeration. If you’re no good at haggling, take a friend who is better.
I bought a mattress (no box spring) a few years ago, and from my experience, you should usually be able to get a mattress for slightly more than half of the stated retail price. Free delivery and removal of the old mattress should be standard, no matter what price you negotiate.
First, find out what type of mattress you like: firm or soft, pillow-top or plain, etc. You have to lie on them for a long time, and in the positions in which you sleep. Relax, take it easy. Take your bedmate so that both of you can try it out. Do you roll in to the middle? Do you like that?
This could take quite a while if you check out a number of mattresses at three or four different stores. They’ll each have different models with different features, and each manufacturer seems to provide each store with its own unique model names, so you can’t get the same model from different stores. Very annoying.
Once you find a mattress you like, find a salesperson and say that you’ll buy that one today for half the price on the tag. And you want free delivery and removal of the old one. If they say no, you say, “Okay. Bye,” and head for the door. As others here have reported, they’ll stop you and make an counteroffer. (If they don’t, leave and go to the next store.)
If they’re willing to sell at half price, you can let them charge you a moderate delivery/removal fee, say $100. But if you pay anything more than half price, free delivery is a must. You should aim for no more than 60% of full price and free delivery. Paying more than 75% is getting ripped off.
Do not buy a box spring if you don’t need it, and don’t let them make it a bargaining point. If they keep trying to sell you a box spring, walk out.
FYI, if you can come out to Columbia, MD, there are three or four stores within a few miles of each other. I got my mattress at Mattress Warehouse of Columbia, MD. They gave me a pretty good price without too much haggling, but I probably could have talked them down a little lower.
Good luck.