Absolutely, visiting Vietnam is a great choice. Here are a few travel tips for your visit to Ho Chi Minh City, Hoi An, Hanoi, and Sapa in Vietnam:

Best Time to Visit:
For Ho Chi Minh City and Hoi An, the best time would be December to April when the weather is warm and dry. While for Hanoi and Sapa, the best time would be October to December and March to April, experiencing cooler, drier days.

Route and Accessibility:
You can reach Ho Chi Minh City, Hanoi, and Hoi An by direct flights. From Hanoi, take a train to Lao Cai then a bus or taxi to Sapa. From Ho Chi Minh City, you can travel to Hoi An by air or train. Domestic flights are available between the cities.

Altitude and Acclimatization:
Hanoi, Ho Chi Minh City, and Hoi An are at low altitudes, but Sapa is in the highland area, so take a day to acclimatize.

Accommodation and Booking:
Book your accommodations in advance. All these places have a wide range of options from homestays, hotels to luxury resorts. Booking.com and Agoda are popular platforms for booking.

Clothing and Essentials:
Light clothing is recommended for Ho Chi Minh City, Hanoi, and Hoi An. Carry a rain jacket as you might experience tropical showers. For Sapa, pack warmer clothing, especially if you're visiting between November and February.

Health and Safety:
Stay hydrated and use sunblock to protect from the tropical sun. Be cautious while crossing roads in Hanoi and Ho Chi Minh City due to heavy traffic.

Local Etiquette and Respect:
Vietnamese people appreciate politeness and respect. Dress modestly, especially when visiting religious sites. Always ask before taking photos of locals. Remove your shoes before entering someone's home or a temple.