Sure, I can definitely provide some travel tips for your planned visit to Buenos Aires, San Antonio de Areco, and Rosario.

Best Time to Visit:
The best time to visit Buenos Aires and Rosario is in the spring (September to November) and autumn (March to May) when the weather is pleasant. And, for San Antonio de Areco, the perfect time to visit would be in November when the Gaucho Festival takes place.

Route and Accessibility:
The most common route to get to Buenos Aires is by flying into Ministro Pistarini International Airport. From Buenos Aires, you can then take a bus or taxi to San Antonio de Areco which is about 113 km away. For Rosario, you can either take a bus or train. It's approximately 300 km away from Buenos Aires.

Altitude and Acclimatization:
These regions are all close to sea level, so there should be no concerns with altitude sickness. Buenos Aires is 25 meters above sea level, San Antonio de Areco is 22 meters, and Rosario is 31 meters.

Accommodation and Booking:
Book your hotels, hostels or Airbnb in advance especially during the peak tourist season. Buenos Aires has various accommodation options ranging from luxury hotels to budget hostels. San Antonio De Areco and Rosario also offer hotels and guest houses.

Clothing and Essentials:
Clothing will depend on the time of your visit. If you're going during the winter (June - August), make sure to pack some warm clothes. If you're going during spring or autumn, light clothing with a few warm layers will be enough as evenings might get a bit chilly. Always carry sunscreen, a hat, and sunglasses.

Health and Safety:
Keep an eye on your belongings in crowded areas. It is recommended to drink bottled water. Make sure to have travel insurance.

Local Etiquette and Respect:
Argentinians often greet each other with a single kiss on the cheek, it's a friendly culture. Argentinians are very passionate about football, showing respect and interest in the sport can be a nice conversation starter. Try to learn some Spanish phrases as it can enrich your experience.