Can you stay in palermo or ricoletto on less than 100 US a night? How many nights should we plan on seeing the city and taking a tango lesson or two? And then where? Mendoza for malbec or Iguazu Fall for how many nights? Would love some advice, since i THINK we're choosing this pricier place over Vietnam? How different is weather in B.A. vs. Mendoza or Iguazu?