You may need a motorbike to explore around the city & beach. But riding a motorbike in Da Nang is challenging. The difficult part for us as foreigners are almost all the signboards, restaurants, display are in Vietnamese which we couldn't understand. No price list for street foods, markets and regular shops which may cause unnecessary dispute. Rarely find local people who can understand or speak English.
Da Nang airport is so near to City Center (within 10 mins) and need not to rush for. If you have more time, Hoi An is another place to look for. There are many new hotels coming along the beach in Da Nang as well as adjacent area which will shape up a new look in 5 years time. Overall Da Nang is a good place to relax by enjoying variety taste of good coffee. Wish I could come back again somedays^^