Hi Stacks,
As others have said, the 06 is a "C" kite and is worth no more than $400 if in really good nick, ie newish. I'd give it the big miss unless you can pick it up at around $350
You should be able to find a 10m SLE 07 for around $600 and an 08 for around 900-1000 if in reasonable condition.
I say a 10m because a 12m "C" is about the equivalent to a 10m SLE/Bow.
Good luck, lots of crappy kites out there,