I worked with Carrot Korea for almost a year. It was a great job! I would have kept doing it if my kids weren't such a distraction while I was on my tutoring phone calls. I didn't have to pay anything to get started.
They paid me through paypal - so I didn't even have to give any banking information. They send you the phones/etc that you need to be able to call your students in Korea so it all goes over the internet, no extra phone bill charge - as long as you have a good internet connection, you are good to go. You basically tell them how much/what hours you can work and they fill your time slot with students. This one is definitely not a scam.