Did this recently for a 6-night stay at a HP. Checked in, stayed the first night, and left after that. On checking in, I advised the front desk that I'd be coming and going and chances were that I wouldn't be in the hotel every night; she didn't seem to care one bit. I hung the DND/room occupied and "forego housekeeping for bonus points" signs on the door when I left, but just in case housekeeping entered, I left an old pair of shorts on the desk chair and some papers on the desk to make the room seem occupied. Checked out online after the sixth night and promptly got credit for all six.