Buses from Argentina to Peru and back

Hi! I am studying in Buenos Aires this-coming summer and after classes I hope to travel via to Cuzco, Peru (going through Chile and the Andes) and back to Buenos Aires, where I will fly home from. I believe I will have 3 weeks to do so and would like to stop at key places along the way-possibly in the mountains to snowboard for a day or two, stopping in Cordoba and other places.

Is this enough time? I was thinking that if necessary I could fly back to B.A. from Lima as opposed to taking a bus.

Does anyone know an approximate price for taking buses one way?

Any ideas regarding where to stop along the way would also be greatly appreciated! In particular, any good places for snowboarding/skiing ?

Thanks a bunch!

Sarah P

3 weeks is way too tight for seeing both the Argentine/Chilean Andes ánd getting all the way north to Cusco. It would be feasible to do either, but not both. Taking a flight back, besides being polluting and quite expensive, won't save you enough time to make it worth doing this.

As to skiing, Las Leñas in Argentina has my preference. But I don't suppose there will be much options during summer.