Do I need to tip in Argentina?

Yes, 10% in restaurants is standard. Tipping is generally done in cash.

Is it safe to drink the tap water?

Yes, it is generally safe in the major cities, but stick to bottled water in remote rural areas.

Should I speak Spanish?

You will get by with English in tourist hubs, but learning basic phrases will go a long way in making connections.

How to plan a two-week Argentina itinerary

Spend 4 days in Buenos Aires to acclimate, 4 days in Patagonia for hiking, 3 days in the Iguazú Falls region, and 3 days in the Mendoza wine country. Use domestic flights to connect these regions to maximize your time, as the distances between these points are vast.

Book internal flights early. Argentina is massive. Use Aerolíneas Argentinas or Flybondi to book internal legs (e.g., Buenos Aires to El Calafate, Mendoza to Buenos Aires) at least 3 months in advance to avoid high prices.
Plan your Patagonia base. Decide between El Calafate (glaciers) and El Chaltén (hiking capital). If you have 4 days, split them: 2 days in El Calafate for Perito Moreno and 2 days in El Chaltén for the Fitz Roy trails.
Coordinate your flight path. Fly internationally into EZE (Buenos Aires). Take your domestic flights out of AEP (Aeroparque) whenever possible, as it is much closer to the city center than EZE.
Manage your currency. Bring crisp, new US dollar bills. Use Western Union to get the 'blue dollar' rate, which gives you significantly more pesos than an ATM or credit card.

Do I need to tip in Argentina?: Yes, 10% in restaurants is standard. Tipping is generally done in cash.
Is it safe to drink the tap water?: Yes, it is generally safe in the major cities, but stick to bottled water in remote rural areas.
Should I speak Spanish?: You will get by with English in tourist hubs, but learning basic phrases will go a long way in making connections.