I was in hotels where even this was not allowed and you had to meet your friend at the reception. On the other hand there are hotels which have more liberal ideas or good relations to the police. I talked to guys on GR and asked them , just for interest, if they knew these hotels and the answer was always, yes , no problems. Vietnamese are quite pragmatic and you can ask directly. There is a well known place in Hanoi, Hoan Kiem Lake where you can find hustlers all the day, just have a seat at a bench..be sure you will be approached soon. But it is always, "ayor". It can be a nice, maybe gay student who wants to practice his English and something more or just a hustler who wants to get you to a karaoke place etc, I would highly recommend to find a guy on GR and ask him which hotel to book etc..........................................

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