I have paid US 38 from the airport to Brickell by taxi.. This did not include gratuities. You can also take the Metrorail orange line until Brickell for US 2.25. in order to take the metrorail, you have to take the mover from the terminal first. This is free. If your hotel is the Hampton inn, then the station Brickell is very convenient. You can search in internet, there are videos that describe how to take the Metrorail from the airport.