First time I bought a mattress I wasn't aware of this. Second time, I got the bedframe, box spring, and mattress protector included, and still managed to knock

First time I bought a mattress I wasn't aware of this. Second time, I got the bedframe, box spring, and mattress protector included, and still managed to knock ~ %20 off the price. I try to negotiate everything now, and have had some measure of success. I will admit that negotiating is mostly, to me, a fun game, rather than a way to save money.