Usually $5 per stay although I agree its much better to tip daily so the person doing the work gets it for sure. Buts it more work for us to remember and get lots of singles.
I recall a stay at the Marriott Orlando World Center where I was so impressed that the maid had propped up my small kids sleeping toys on their pillows each day that I wanted to leave a large tip when departing on a Saturday. I ran into a maid in the hallway when leaving and asked if she had been servicing the room all week. She muttered an unfriendly and gruffly "yes" and I gave her the tip anyway but I really had my doubts since the personality didn't jive with the action.
I'm definitely in the camp that people should do their jobs regardless of tip motivation and we have gotten to a level of where its expected regardless of actual delivery, especially in the restaurant and livery trades. And employers should build their true labor costs into their products - $250 a night for a room and they can't afford to pay their staff appropriately? Not to mention the whole cash / tax avoidance issue. I'm no fan of paying taxes but I have no opportunity to hide a % of my W-2 income from taxation. Didn't the skycaps at Boston Logan successfully sued American Airlines when they imposed a service fee instead of tipping that cut into their income tremendously - and the stories of what they can make?
Usually, this will provoke a response like "you never worked where you had to rely on tips" but this isn't true as I delivered newspapers from 11-16 years old and tips were a big part of my meager earnings for maybe $15 a week total. It was tantamount to child slave labor and I was too young to realize it being out in the elements 8 days a week. Try and find a paper boy today !
I'll leave nothing if there is any issue like not leaving new shampoo and mouthwash daily.