I finally made it to Argentina! I may not have time to write a real TR, so I'll add some information here:
1) We flew JFK - GRU, and had an 11 hour stopover. We hired a guide who picked us up (and had room for our luggage) and drove us around for 7 hours. We basically all the sights of the city. Sao Paolo is nice, but 7 hours was mostly enough.
2) We flew GRU - IGU and had transportation arranged through the hotel to get to the Gran Melia. You have to get out of the car at both Brazil and Argentina border control. The Gran Melia is gorgeous and the most shabbos friendly hotel I've ever stayed at (with the exception of room keys). We did a day on the Brazil side - we took a bus tour of the Itaipu Dam (I couldn't convince my travel partners to take an engineering tour), went to the bird park, the boat ride and the trails at the falls. The nice part of the Brazil boat ride is that you can opt for a dry boat - you get close to the falls but not get soaked. We hired a driver/guide for this which allowed us to get through customs much faster and stay in the park later.
3) On the Argentina side, you do not need a guide at all. If anyone in your party has any sort of limitation, you cannot take the boat ride. Argentina in general is very friendly to individuals with disabilities including discounts for the individual and often for a companion. The trails are easy to walk on; they are mostly metal platforms.
4) We went to Salta Sunday to Wednesday. Aerolinas Argentina has non-stop flights on Sunday from IGR. With delta status, we got 23kg luggage instead of 15 kg. In Salta, we stayed at the Sheraton. It's a beautiful hotel with great views of the city because it is on a hill; the hotel has a beautiful rooftop pool. The hotel is walking distance to the main square and the cable car. We went to the salt flats one day (it's a bucket list item for me but I don't know if I will ever get to Bolivia; this one is much smaller but didn't disappoint) and the Las Cordones National Park and Cachi the next. Our last morning, we went to the cable car, which has great views of the city. We used Tangol for our tours and they were excellent and have whatsapp for communication.
5) Next we hit Buenos Aires. We stayed at the Sheraton. It was also very shabbos friendly - we got a room on the third floor and the stairs were easily accessible. In BA, we went to the Tigre delta, did a city tour, walked through the cemetary and went to Uruguay for the day. We ate out at Al Galope, Ioko Sushi, La Empanaderie, Luba's Cafe and McDonalds. Al Galope was very good (cash only, will take USD), Ioko Sushi had amazing sushi (takes CC), La Empanaderie (cash only, took USD and gave us the blue dollar rate) had delicious empanadas, Luba's Cafe (delicious but we just got some desserts, they take CC) and McDonalds was disappointing because it wasn't terrible (they take CC). We went to Chabad Recoleta for Shabbos and had a really nice lunch with their community and of course met other Jews from NY.
I was surprised at how much of a cash society Argentina is. We usually just use credit cards everywhere, but the exchange rate was drastically different. If you bring $100 US bills, you get a much better exchange rate on the black market.
