asked a friend what she does and she said, on the 1st day she will leave say $2 or so in a book as abook mark right on the bed, when she gets back if its been taken then they got all they are going to get. If on the other hand the book was moved to say onto a Table next to the bed and the $2 is still there then she will tip for each and every day, or $20 for a week.

right or wrong, she feels let Housekeeping decide for her if she'll tip or not, if there for 1 night she doesnt tip unless she really bothered them or made a real mess.