It says the "round trip" is ~&150-300. So half that for one way.
Discussion
OH! that’s actually substantially better than what I thought. Should’ve read closer
A local told me that at one point, Brightline was offering free shuttles (in a Tesla) from the train station to your destination (within some predefined radius) for trips between west palm beach and Miami.
So it's convenient if you're visiting family or someone with a car at your destination.... otherwise, you're stuck ubering everywhere at your destination.