Join Date: Jan 2010
Location: Calgary, Alberta
Programs: Hyatt Diamond, Fairmont Platinum, Aeroplan Diamond, HHonors Gold, SPG Gold
Posts: 18,686
The general rule I follow is the tip is paid when the transfer service is paid. If its prepaid, then I would assume the gratuity is prepaid. I would usually pay in the 15% to 20% range on exceptional service, although it is on the generous range.