Originally Posted by MJM
Costs are paid all at once, not one by one. You can't pay the cost of a (3) Jutsu if you have 2 cards left in deck just like you can't pay the cost of a (3) Jutsu if you have 2 Chakra.
That's what I thought. IM not the only person who likes proof of everything though. I couldn't find it q+a or in advanced rulings though.