Those of you who have spent time on Reddit and other social networking sites have probably seen ads about sites with Uber and cab fares. If you would like to add a taxi fare calculator to your website, Cab Grid is worth a shot. It lets you add areas and prices for each region to the backend. Currency and styling options can also be modified easily.
You will be able to display the calculator via a shortcode or as a widget. The plugin supports custom messaging. You can try the Basic Edition here.