Any one from bell services that touches my bag (taking it when I check in, delivering it to the room, picking up from the room, or loading the car--all of which might be different people) gets $1 per bag or parcel, more if they are bulky or heavy.
I leave $5 per day for housekeeping, $2 per day for turn down srevice.
Valet parking I give $2 when I drop off and $2 when i pick up.
I also bring a gift for the concierge staff.
Of course I also tip servers and car srevice drivers--20% is generally teh minimum, more for exceptional service.
Anne