It is a $500 LIMIT PER DAY according to this
. Once you reach your limit, RCI will contact you to let you know you've reached the daily limit.
2007 - Majesty of the Seas (Bahamas)
2009 - Enchantment of the Seas (Western Caribbean)
2010 - Freedom of the Seas (Western Caribbean)
2013 - Golden Princess (Alaska, roundtrip from Seattle)