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"Spring is definitely the best time to buy a mattress and Memorial Day is the best time for sales," Perez says.
You'll see storewide sales of 20% to 40% off all weekend, she says. Add to that store coupons for an additional 10% to 40%. Take in all the discounts, and you could get a mattress for 60% to 75% off, she says.
Perez's advice: "Look for 50% minimum off over Memorial Day weekend." Mattresses have wide price margins, so there's plenty of flexibility on the price, she says.
Mendelsohn says the discounts will be a little less -- 20% to 30% -- "unless it's something they want to get rid of," she says.
Perez points out that most of the bigger department stores offer free delivery, so that's definitely something to ask for, she says.
"Haggle that price down and talk about the extras like haul-away and delivery," she says.