But according to Jacquie Denny, co-founder of online estate sale company Everything But the House, you could be making a costly error.
She believes that people forget to consider the resale value of some of their items.
"I always tell people that as soon as someone calls me and says either 'my mom doesn't have anything' or 'she has the ugliest art I've ever seen,' I want to go to that house," she told Apartment Therapy.
She says that when considering the value of something, it really depends on two things: condition and rarity.
So what should you keep, and what should you toss? Apartment Therapy gets her expert opinion on the things you shouldn't be chucking.
If you’ve collected a china ‘pattern’ over the years, it might be worth hanging on to it.
"When you talk about china on a broad scale, it's not as valuable as it used to be because people entertain more casually now, but there are still stars," say Denny. Brands like Royal Albert, Royal Doulton and Wedgwood have resale value.
It might be worth hanging on to your beloved toys, as long as you’re strategic about it, rather than sentimental.
"I can't tell you how many parents who had kids in the '60s and '70s will say 'these are all my kids' old Star Wars stuff, their old toys,'" says Denny.
"I've sold Star Wars Lego sets mint in the box from the '70s for $800."
Keep an eye out for iconic pieces that represent a particular time or place, but don’t hang on to anything unless it’s in mint condition.
"If you've got a Fisher Price See n' Say that has the labels worn off and it warbles when you pull the string, there's probably no value," says Denny.
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Mid-century pieces will always attract buyers, and hang on to any designer items like Australian Parker furniture.
"Furniture in general is the safest it's been historically," says Denny.
"The reason for that is that we're the largest generation in history with the most people passing away and making a downsize. There's way more furniture in the marketplace than is being absorbed."
Before you ditch your gran’s old rug in the hallway, consider its value. According to Denny, hand-woven rugs have never been more popular.
"People want area rugs for the first time in 20 years."
Just make sure you’re hanging on to a quality rug in excellent condition.
According to Denny, items like early iMac and Apple computers can go "for thousands of dollars.” Have a look on eBay and find out what your machine is worth.
If you have an old record player, think again before throwing it out. Vinyl records are having a renaissance, so collectors will pay good money for a vintage record player in good condition.
"I always tell people to keep their children's books because when we go to start reading to our children, we remember them," says Denny. "Reading from the original books are so much better."
Apart from the sentimental value of books, they can also fetch a pretty penny. Keep any first editions or anything signed by a popular author.
It can be hard to part with sentimental items, but boxes of keepsakes can take up a lot of room in storage. So how do you decide?
According to Denny, "If it's an item that's sentimental, or has a family history to it, I encourage them to keep it unless the family gets into the situation where they need to sell a historical piece.”
However, she cautions that “If you're not going to display it or see it or share it, if it's just going to sit in a cabinet, sell it and put the money in an account and go on a trip together."
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