The e-commerce site eBay was started with the simple idea that one person’s trash is another’s treasure. It’s also a great way to make money and avoid sending things you don’t want to the landfill. But when it comes to heavy items like furniture, eBay is not a great option, since heavy items are expensive and difficult to ship. Instead, look at local used-item sites like Craigslist, FreeCycle (where every transaction is totally free) and even growing companies like Kaiyo, which picks up your furniture and sells it for you.

https://www.dailycourier.com/arts_and_entertainment/do-just-one-thing/article_569d4e52-5dd3-11ed-a49e-3f382148feb7.html

You can give mattresses away via a local gifting group, like Buy Nothing or Freecycle.  

https://shrewsburyma.gov/CivicAlerts.aspx?AID=7056

Freecycle:
This website is all about keeping things out of landfills. Here, you can find everything from clothes to appliances to building materials. Freecycle is perfect if you’re looking to upcycle or repurpose something.

https://q1057.com/save-money-by-scoring-freebies-in-the-capital-region/