Below is a good thread from a couple of years ago about where ladyboys live in Bangkok along with some pics. Just click on the link.
TF girls - at least the p4p ones - will usually go wherever you want as long as the money is right.
I don't know about the hotel, but that won't be your real problem if you are taking girls from Sukhumvit area. Many LBs will frown on traveling all the way to Chinatown, particularly for short time. When they leave your room, they will request an absurd amount of "taxi money" and God help ya' if you disagree with the figure they want.
You may be better off just using a short time room in Sukhumvit. If you don't like short time rooms, you can book a budget hotel room at Heaven @4 or wherever for a few nights to be used for your mongering activities and then return to your "real" hotel room in Chinatown at the end of the evening or the next day.
