Spell copying

[Oldschoolmtgnoob]

I think this kind of question gets asked a lot, but I couldn't find it quickly and I'm lazy so sorry for the redundancy...
I cast {howl of the horde}, and then {hordeling outburst}, do I have to pay for the two copies as well as the original cost, for a total of 12 mana? (Including HotH). Or do the two copies come free, totalling 6 mana?

[Millionlittlee]

The two copies are free totaling 6 mana