Try a search with Kayak or Skyscanner using flexible dates and all airports for the cities involved. This should show the cheapest fare and let you decide the most suitable one.
In the US, Miami - Kansas - Miami is more expensive than Kansas - Miami - Kansas. The reason is that someone going from Kansas to Miami is going on holiday and can easily switch to another destination if he doesn't like the price where as someone going from Miami to Kansas is going there for a specific reason and can't go elsewhere.