Money for Nothing

This 28-year-old made $2,400 in 4 months selling things online—here are her top 4 tips

At the start of 2018, Dallas Wolford felt inspired to declutter. "I realized I had all these things I didn't need," she tells CNBC Make It. Rather than tossing old clothes, kitchenware and tech gadgets, she decided to try to sell them.

Having just finished med school, "I hadn't been making money," the 28-year-old says. "I'd just been spending a lot of money on education. And with that mounting debt, I wanted to slowly chip away at bills and school loans, so I created a huge pile of things to sell."

She downloaded the selling app Mercari and started listing "a huge array of things. Anything from Nike tennis shoes to Kendra Scott jewelry." By April, after minimal effort and just four months of posting items on the app, she had an extra $2,400 in her bank account. The fact that the process was so efficient was important: After all, "time is a luxury and not something I have a lot of," says Wolford, who is currently studying for the boards.

If you're looking for an easy way to make some extra cash, follow Wolford's top tips for selling anything in your closet or garage online.

1. Sell the small stuff

Wolford's impressive profit this year "is not all from big ticket items," she says. "I did sell one laptop, but some of my items sell for just $10."

Sales of kitchenware or clothes can add up: "Say you sell something for $10. After shipping and the seller fee, you'd maybe have $6. If you sell one item a day, after 10 days, you have $60 in your account that you would not have before. After 15 days, you'd have almost $100."

Even if you don't earn thousands like Wolford has, an extra $60 to $100 is still something: "When it comes to those little items, I think people oftentimes think it's not worth selling. But think of what you could do for your kids for $60? Or what could you buy for your husband for Valentine's Day that you couldn't before."

28-year-old Dallas Wolford
Courtesy of Dallas Wolford
28-year-old Dallas Wolford

2. Give lots of detail

Wolford has found that items are more likely to sell when she includes a description with specific details, like the brand of the item. "People want to know exactly what it is they're buying," she says, adding that brands such as Nike, Lululemon and Patagonia sell quickly.

3. Be open-minded

"I can't tell you how many things I've sold that I literally thought, 'Nobody is going to buy this,'" says Wolford. "I had athletic shorts that had paint on the side and somebody bought them. I don't think people realize that somebody will find value in things that you don't find value in anymore."

Plus, "you have nothing to lose other than a minute of time from uploading it, and potentially $5 to $50 to gain."

4. Don't delay

"The biggest thing is to just dive in and not put it off for later," says Wolford. Make a goal of selling one item a day, she says. And if you're having a hard time collecting things to sell, try following Wolford's rule of thumb: "If you haven't used it, touched it or worn it in a year, it's got to go. Don't hang onto things because you think you're going to use it. If you haven't used it, you're still not going to use it."

There are other apps besides Mercari that make it easy to sell used items, including Letgo and OfferUp. If you're selling clothes, shoes and accessories, try sites like Poshmark, thredUP and TheRealReal.

Keep in mind that even if your apartment is clean and tidy, chances are "there is a bunch of stuff you don't use that somebody else could find valuable," says Wolford.

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Video created by Richard Washington.