How hard is telemarketing, and how much do youmake

I have a interview tomorrow for a telemarketing job, but I was wondering if the job was easy? I mean, sitting on your bum for hours talking on the phone while getting paid seems to easy and I know there HAS to be a catch! Unless the outside of the box really does look the same on the inside. Also, when you first start off, how much do you make?
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telemarketing service