Taylor says, "They're re-selling instruments all over the world and so they're going to be buying a much greater variety."
And if you have electronics to sell, you might try eco ATM, an actual kiosk that will take your old electronics on the spot and give you instant cash.
Fauth says, "I put the phone in and they quoted me 146 dollars, which was pretty good."
Of course with the convenience there is a cost, with each site taking a cut.
"You're paying a lot more in commissions than you would with a site like Craigslist," says Taylor.
But Carly says for her, it's worth paying a little extra to get it all off her hands.
Fauth says, "Just finding a way to get rid of stuff and make money at the same time, it's just, to me it's a great feeling."
Experts say the payout you get from these sites can vary widely and consumers should shop around for the best offers for their goods. And while commissions may be higher than just selling directly on craigslist or Ebay, they tend to be less than some brick and mortar consignment shops.