if you want incall (she gets the room)and you leave at the end of the appiontment. Or outcall you get the room and she leaves and the end of it.

Although I have never done an overnight myself it was my assumption that it is our responsibility to pay for the room for an overnight.

Like you said in-call is her, out call is you, overnight is you as well. Hey at the rates you pay for an overnighter the cost of the room is kind of sweating the small stuff.