Discussion about Florida passenger rail operations including proposals. Official web-sites:
Miami/Dade Metrorail, Sunrail (Orlando), and Tri-County Commuter Rail Authority
For Virgin Rail/Brightline: Virgin Trains Worldwide (includes Brightline)

Moderator: Kurt-Trirail

  by rail10
Does miami metromover and miami metrorail uses turnstiles or fare barriers for paying fares?

  by chrsjrcj
I am not sure but I do know that the metromover is free.
  by Ocala Mike
Of course, it's the South Florida Tri-Rail, not just Miami. There are no turnstiles; in fact Tri-Rail shares some of its stations with Amtrak. From the schedule:

"Tickets must be purchased before oarding the train. Tickets are
not sold onboard trains. Tri-Rail fare inspectors randomly check
for proof of ticket purchase."

  by sery2831
Metrorail uses turnstiles and tokens.