Money: Check with your bank: some US banks are partnered with foreign banks and will not charge you fees for using those ATMs.
Weather: In June (for La Plata): Average temperatures: 58 high / 42 low. Average rainfall: 2.2 inches
IPO 24 Hour Emergency Number: +1(602) 220-1372
Call your bank and credit card companies to inform them you will be out of the country and using your cards abroad, so they don’t freeze them.
Taxis and most restaurants do not accept credit cards, so you will need to carry cash with you. They also do not usually speak English.
A bank called Santander Rio is common, and their ATMs have an English option. They will charge you about $4 per transaction.
In La Plata especially, be careful walking the city: cars do not stop for pedestrians, and intersections without stoplights have a vague rule about right of way, but are otherwise without traffic control. And people tend to drive fast and close.
You can hire a metered taxi, or a set-fee “remise” to take you from La Plata to Buenos Aires or the airport (or vice versa). There is also a bus that will take you to and from La Plata.
At LAX, for example, you have to walk outside to the international terminal, or take a bus there. You may consider looking up the layouts of the airports you will be using in advance.