When purchased sufficiently ahead of time, airfare is usually pretty close to bus fare in Brazil.
My trip is 1 month away. Nothing available cheaper than US $220.
I'd still do that rather than the bus.
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if you haven’t driven in Brazil, you probably don’t want to/shouldn’t.
Is it worse than driving in Indonesia/Thailand?
Do they stack up 5 cars coming at you in your lane at 110+ kph (trying to pass the car in their lane, 1 lane each direction, no shoulder) in Indonesia/Thailand? Common practice in Brazil.
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There is local bus transportation and taxis to get around the park area.
Does it make a financial sense to rent a car to see both sides, or taxis/buses would be sufficient?
Taxi or local bus will do fine.
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Stay on the side you are flying OUT of.
Rather than - leaving from.
BTW, the site shows that bus route crosses Argentina before going back to Brazil. Does this mean that there will be passport check stops twice?
What site?
Never took a bus to Foz, so can't comment.
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Cash. Reais for Brazil. Pesos for Argentina.
How much is entrance fees at this moment? Where one can get pesos from ATMs at Argentine side safely? I mean without card skimming risk?
Official park sites for entry fees and other park info:
https://www.cataratasdoiguacu.com.br/
http://www.iguazuargentina.com/en/
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Presumably you have a visa in your US passport for the business trip.
I don't. I am travelling there on a passport which does not require visa from Brazil.
But does require a visa from Argentina?
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Buses to the falls area carry Brazilians going to Cidade del Este in Paraguay with lots of cash to buy merchandise for their small shops. Robbers know this. These bus routes are vulnerable, especially after dark.
All buses or just some particular one? If I do not intend to go to Paraguay but only want to go to Argentina, what should I do?
Point to a bus heading in the direction of the falls that doesn't have any of these "moambistas" as they are called. Can't? Neither probably can the thieves.
(Check TA and Thorn Tree for the recent story of one traveler who just got caught up in this on another route.) Night buses are most vulnerable.
What should you do? Fly, IMO.
Can you get a flight through Curitiba more cheaply than direct?