The approximate prices for a vacation in Hanoi are as follows: Hotel - $30-100 per night. A tour to a palace or temple can cost between 25,000 and 320,000 VND, with long-distance and full-day water excursions with meals costing around 1.5 million VND.
According to reviews about vacations in Hanoi, meals won't be ruinous either: for 150k VND you can get an excellent tasty lunch with drinks. Of course, there can be significant variations up and down depending on the class of establishment where you choose to dine.
With prices for souvenirs starting at 85 thousand VND, shopping is a great deal here.
Transportation costs. If you will rent a car, expect to pay an average of 1-1.5 million VND per day, a moped will cost 200-230,000 VND, a single bus ride will cost 5,000 VND, and a ten-minute ride with a cycle rickshaw will cost 15,000 VND.
As for the other expense items, it all depends on the purpose of your trip. In any case, a romantic vacation for two in Hanoi or a vacation with children will be much cheaper than in Europe.