Flew from the Philippines with two friends to Hanoi, Vietnam with nothing more than backpacks. Met up with another friend and purchased motorcycles the next day. Drove for a day to the coast of Ha Long. Headed south until we eventually reached caves in the jungle of Phong Nha and were joined by two more friends. Six friends rode off into the heart of the jungle for a day until coming out and staying in Khe Sanh for a few nights. After that we hit a few major cities each night along the coast until we ultimately sold our motorcycles in Hoi An and bought flights to Ho Chi Minh City for only $25. After Ho Chi Minh city it was off to Cambodia with only our backpacks. Every step, and ride, of the way was a total unknown adventure. Every day was more fun than the last. From sunshine to typhoons, every day was humid. Showers came few and far between, but the amazing bowls of pho stayed constant throughout the journey—as did the local coffee. Would I do it again? In a heartbeat!
Buying a motorcycle for the trip is smarter than renting. The live animals you see running around the streets are likely the animals they will be serving in your pho.