YoYo27

Westin Grande near Asoke BTS is around 5.5 k baht per night. 6.5 with breakfast. If you book early, have Marriott membership you could use points etc. And bring it down.
Great rooms, all facilities, location is quite convenient ( 7-8 min to CIB, 12-15 for Cindy's). Lobby is on 7th floor. So ask the girl to come there. And then get her through the access elevators or leave a message and they will allow her to your floor.

Landmark and Sofitel are great hotels. 
But for the same prices you will get a much bigger room in Mercure soi 11 or Adelphi Suites soi 8 - I would say 30 sqm / 50 sqm - 
Depends what you prefer (I prefer the bigger room).
 
Discreet ???  Are you scared of being seen by someone you know with a ladyboy while coming back to your hotel ? Well ... It can happen. I once met a work mate in Nana Plaza. I didn't know he was in Thailand. I was alone, just coming back from a short time session with a ladyboy in a Nana Plaza short-time room. Hmmm.
To avoid that :
- Take a session in the short time room of the bars (Cindy's, CIB, Chaos 9, Why Not all have short time rooms upstairs).
- Barfine the girl and tell her to be in 30 mins at your hotel. Give her your room number. Come back first to your hotel and tell the receptionist a guest will be there soon and that she can go up to your room.
- Book a girl with Smooci or another escort agency or Thaifriendly. She will go to your room.

I was a little bit dissapointed with Landmark during my stay, maybe the fact that i think the executive lounge was a big joke. I did like the rooms at Mercure soi 11 more, just opposite of Cindys. Aloft is decent as well. Personally i would pick Mercure or Aloft instead of Landmark on my next visit.

I understand they have their policies when it comes to early check in or late check out.
At Aloft i arrived 7 hours before check in because of early flight. They didnt have any problem to find me a room, plus they also gave me a free upgrade for no extra charge. While on the other hand, Landmark i asked for late check out (3 hours later than my check out time). They were going to charge me for a half day extra for late check out.

Landmark ! Hands down.