I'm out of my depth here

I'm considering a little venture into wood carving/engraving. I've seen this benchtop i Carver 1520 at my local http://ift.tt/1TPZ5x7 for $4,750 which I'm comfortable with and can take immediate delivery of it. So as per the post title "I'm out of my depth" and would like to tap into the wisdom of you fellow members on: what should I be looking for in regards to the attributes of a CNC? the quality level of this i Carver? are the cheaper ebays just as good? the number of axis what are they and what do they do? and from here I don't really know what else to ask so hopefully you will tell me. Thanks in advance - Rod