Taxi's from MIA to the #### are a flat rate of $24. Another option is Super Shuttle for pricing ($14pp). For us we prefer just jumping in a cab and GO.
If you are leaving from a #####, the shuttle option might be cheaper. You can ask the concierge.
I tried to add a link here for the miami ####### but it didn't work. If you do a search on the website it shows the pricing and trans####ation options