I leave the tip out every morning. I tip $10 but there are 5 of us in a 2 room suite with 4 beds and 2 bathrooms to clean. If it is just myself and my husband I leave $5. I would never leave less than $5.
But it shouldn't be too long, someone will come along to let you know that housekeeping is not a tipped position and you don't need to tip them.