If you travel to Hanoi, highly recommend Nhac Duong Lau. Not really close to the old quarter, but best in terms of service and facilities. Much better than the extra you get at your hotel massage (every hotel has one). If you have telegram, you'll see which girls they have on the day much like the roster here in NZ. When you come there will be a foot massage, and they'll give you an ipad with photos of all girls available that day. The foot massage lady will probably try to wank you off for a small tip (~vnd200k or $10), up to you. Then you pick the girl and come up to the room, start off by a sauna and in 5-10 minutes the girl will come in. Try to get out of the sauna have a look and if you want to change , now's the time. Then it's bath time and you will have a bath where the girl clean you top to toe, even washing your hair and drying it after. Then the sensual massage. As a rule of thumb the tip will be exactly the same as the fee, say vnd2m for 1 hour, then you're expected to tip the same to the girl. You'll tip at the very end. The girls will have to share part of their tips to the management as well, how much depending on the place. Except for full service which is strictly prohibited in every massage place, most girls will allows everything considered extras here in NZ. Normally intimate touch, kissing, and non covered BJ. 99.99% they don't speak English, but probably not that big a deal.
This applies to almost all other massage places in big cities, facilities may be better or worst. If you want to stick to hotel, pick the big ones. Bigger hotels tend to have better girls, but nowhere near the dedicated SM place like Nhac Duong Lau. You can also google or chatgpt nhac duong lau alternatives, heaps of them.