New York City
ABuenos Aires: Neighborhoods recommendation to live in Buenos Aires 3-5 months
Recoleta, Puerto Madero, Palermo. I liked recoleta a lot.
AZurich: Zurich cheap pubic transportation?
sounds like a solid plan you have :) usually www.sbb.ch is the website to book public transportation. furthermore Zurich has uber, which might be less expensive when you have enough people sharing car costs.