I think Super Shuttle cost us $32/pp Miami to Ft. Lauderdale.
Looking at the map it seems you could take the light rail system from FLL to Miami but you would still have to take a cab to South Beach. Can any South Floridians weigh in on the light rail system?
A Bad Day At Sea [with power] Always Beats A Good Day At Work
Carnival: Glory 2004, Destiny 2008, Splendor 2009, Freedom 2011, Valor 2012, Dream 2013
Celebrity: Summit 2011
Princess: Ruby 2010, 2014, Caribbean 2013, Coral 2014