To do it in two weeks, you're basically going to have to go in there ready to rock. Have your binder ready, have your regs memorized and be automatic on the FOI. In two weeks you basically get a flight or two for each check ride and a little bit of brush up.

Didn't go to ATP but know a lot of people that did for the CFI program. Regardless of where you do the CFI the cost will be totally dependent on your preparation.